Honeybees are disappearing for unknown reasons around the United States．Last winter, bees disappeared from 23 percent of American beekeeping businesses．Causes of the phenomenon, however, have remained a mystery．

       Now, scientists from several universities and the United States Department of Agriculture say they have a possible explanation for the bee decline（数量下降）．It is a little known virus called Israeli acute--paralysis virus （IAPV） ．The virus kills bees．Researchers in Israel first described it in 2004 , but until now, bee experts hadn’t paid much attention to it．

       When trying to find out why the bees were disappearing, a research team at Columbia University studied bee colonies （ 群体）, some with and the others without decline．The research turned up large numbers of two types of fungi （真菌） once suspected of causing the bee decline．The research results, however, showed that the fungi were almost as common in colonies without a decline as they were in colonies with a decline．The researchers concluded that the two fungi probably weren’t the cause．

       Studies of the presence of IAPV, however, showed more interesting information．In those studies, done by a team at Pennsylvania State University in University Park, the virus showed up in 83 percent of samples from colonies with symptoms （症状）．Only five percent of samples from symptomless colonies had it．

       Scientists still don’t know whether IAPIV can single--handedly cause the bee decline．They believe that even if the virus is making colonies sick , it could have a partner in crime．It’s possible, for instance, that insects or chemicals in the environment weaken bees, making them more likely to catch IAPV．

       Scientists are still trying to figure out how IAPV came to the United States．The United States currently allows bee products to be imported from Canada, Australia, and New Zealand．If it turns out that this trade is spreading disease, the rules might eventually change．

According to the passage ，IAPV is a virus that ______．

       A．hasn’t attracted much attention

       B．well-known to doctors and scientist

       C．was first found by Austrian researchers

       D．is dangerous to animals and human beings

The underlined sentence in the fifth paragraph probably means______．

       A．the virus could also cause other damages

       B．there must be something that is the real cause

       C．IAPV is not the only cause for the bee decline

       D．the virus may be caused by the polluted environment

From the third and fourth paragraphs, we know researchers draw their conclusions by means of _______．

       A．calculating      B．comparing      C．examining           D．investigating

What still remains unknown to American scientists according to the passage?

       A．How and why to kill IAPV．

       B．How IAPV came to America．

       C．Whether bee products should be imported．

       D．How to change the rules of the bee products trade．

The best title for this passage would be _____．

       A．Bee Disease         B．How to Kill IAPV

       C．A Virus—IAPV     D．Two Types of Fungi

ROME: The legend of Leonardo da Vinci is covered in mystery: How did he die?Are the remains buried in a French castle really those of the master? Was the "Mona Lisa" a self-portrait in disguise (伪装)?
A group of Italian scientists believe the key to solving those puzzles lies with the remains, and they say they are seeking permission to dig up the body to conduct carbon and DNA testing.
If the skull is undamaged, the scientists can go to the heart of a question that has fascinated scholars and the public for centuries: the identity of the "Mona Lisa." Recreating a virtual and then physical reconstruction of Leonardo's face, they can compare it with the smiling face in the painting.
"We don't know what we'll find if the tomb is opened. We could even just find grains and dust," says Giorgio Gruppioni, an anthropologist who is participating in the project. "But if the remains are well kept, they are a biological record of events in a person's life, and sometimes in their death." Silvano Vinceti, the leader of the group, said that he plans to press his case with the French officials in charge of the said burial site at Amboise Castle early next week.
Leonardo moved to France at the invitation of King Francis I, who named him "first painter to the king." He spent the last three years of his life there, and died in 1519 at age 67. The artist's original burial place, the palace church of Saint Florentine, was destroyed during the French Revolution and remains that are believed to be his were eventually reburied in the Saint-Hubert Chapel near the castle.
"The Amboise tomb is a symbolic tomb; it's a big question mark," said Alessandro Vezzosi, the director of a museum dedicated to Leonardo in his hometown of Vinci. Vezzosi said that investigating the tomb could help identify the artist's bones with certainty and solve other questions, such as the cause of his death. He said he asked to open the tomb in 2004 to study the remains, but the Amboise Castle turned him down.
The group of 100 experts involved in the project, called the National Committee for Historical and Artistic Heritage, was created in 2003 with the aim of "solving the great mysteries of the past," said Vinceti, who has written books on art and literature.
Arguably the world's most famous painting, the "Mona Lisa" hangs in the Louvre in Paris, where it drew some 8.5 million visitors last year. Mystery has surrounded the identity of the painting's subject for centuries, with opinions ranging from the wife of a Florentine merchant to Leonardo's own mother.
That Leonardo intended the "Mona Lisa" as a self-portrait in disguise is a possibility that has interested and divided scholars. Theories have existed: Some think that Leonardo's taste for tricks and riddles might have led him to hide his own identity behind that puzzling smile; others have guessed that the painting hid an androgynous lover.
If granted access to the grave site, the Italian experts plan to use a tiny camera and radar to confirm the presence of bones. The scientists would then exhume (挖掘) the remains and attempt to date the bones with carbon testing.
At the heart of the proposed study is the effort to discover whether the remains are actually Leonardo's, including with DNA testing.
Vezzosi questions the DNA comparison, saying he is unaware of any direct descendants (后代) of Leonardo or of tombs that could be attributed with certainty to the artist's close relatives.
Gruppioni said that DNA from the bones could also eventually be compared to DNA found elsewhere. For example, Leonardo is thought to have rubbed colors on the canvas with his thumb, possibly using saliva (唾液), meaning DNA might be found on his paintings.
Even in the absence of DNA testing, other tests could provide useful information, including whether the bones belonged to a man or a woman, and whether the person died young or old.
Even within the committee, experts are divided over the identity of the "Mona Lisa."
Vinceti believes that a tradition of considering the self-portrait to be not just a faithful imitation of one's features but a representation of one's spiritual identity may have resonated (共鸣) with Leonardo.
Vezzosi, the museum director, dismissed as "baseless and senseless" the idea that the "Mona Lisa" could be a self-portrait of Leonardo. He said most researchers believe the woman may have been either a wife of the artist's sponsor, the Florentine nobleman Giuliano de Medici, or Lisa Gherardini, the wife of a rich silk merchant, Francesco del Giocondo. The traditional view is that the name "Mona Lisa" comes from the silk merchant's wife, as well as its Italian name: "La Gioconda."  
【小题1】   Where is this passage most probably taken from?

ROME: The legend of Leonardo da Vinci is covered in mystery: How did he die? Are the remains buried in a French castle really those of the master? Was the "Mona Lisa" a self-portrait in disguise (伪装)?
A group of Italian scientists believe the key to solving those puzzles lies with the remains, and they say they are seeking permission to dig up the body to conduct carbon and DNA testing.
If the skull is undamaged, the scientists can go to the heart of a question that has fascinated scholars and the public for centuries: the identity of the "Mona Lisa." Recreating a virtual and then physical reconstruction of Leonardo's face, they can compare it with the smiling face in the painting.
"We don't know what we'll find if the tomb is opened. We could even just find grains and dust," says Giorgio Gruppioni, an anthropologist who is participating in the project. "But if the remains are well kept, they are a biological record of events in a person's life, and sometimes in their death." Silvano Vinceti, the leader of the group, said that he plans to press his case with the French officials in charge of the said burial site at Amboise Castle early next week.
Leonardo moved to France at the invitation of King Francis I, who named him "first painter to the king." He spent the last three years of his life there, and died in 1519 at age 67. The artist's original burial place, the palace church of Saint Florentine, was destroyed during the French Revolution and remains that are believed to be his were eventually reburied in the Saint-Hubert Chapel near the castle.
"The Amboise tomb is a symbolic tomb; it's a big question mark," said Alessandro Vezzosi, the director of a museum dedicated to Leonardo in his hometown of Vinci. Vezzosi said that investigating the tomb could help identify the artist's bones with certainty and solve other questions, such as the cause of his death. He said he asked to open the tomb in 2004 to study the remains, but the Amboise Castle turned him down.
The group of 100 experts involved in the project, called the National Committee for Historical and Artistic Heritage, was created in 2003 with the aim of "solving the great mysteries of the past," said Vinceti, who has written books on art and literature.
Arguably the world's most famous painting, the "Mona Lisa" hangs in the Louvre in Paris, where it drew some 8.5 million visitors last year. Mystery has surrounded the identity of the painting's subject for centuries, with opinions ranging from the wife of a Florentine merchant to Leonardo's own mother.
That Leonardo intended the "Mona Lisa" as a self-portrait in disguise is a possibility that has interested and divided scholars. Theories have existed: Some think that Leonardo's taste for tricks and riddles might have led him to hide his own identity behind that puzzling smile; others have guessed that the painting hid an androgynous lover.
If granted access to the grave site, the Italian experts plan to use a tiny camera and radar to confirm the presence of bones. The scientists would then exhume (挖掘) the remains and attempt to date the bones with carbon testing.
At the heart of the proposed study is the effort to discover whether the remains are actually Leonardo's, including with DNA testing.
Vezzosi questions the DNA comparison, saying he is unaware of any direct descendants (后代) of Leonardo or of tombs that could be attributed with certainty to the artist's close relatives.
Gruppioni said that DNA from the bones could also eventually be compared to DNA found elsewhere. For example, Leonardo is thought to have rubbed colors on the canvas with his thumb, possibly using saliva (唾液), meaning DNA might be found on his paintings.
Even in the absence of DNA testing, other tests could provide useful information, including whether the bones belonged to a man or a woman, and whether the person died young or old.
Even within the committee, experts are divided over the identity of the "Mona Lisa."
Vinceti believes that a tradition of considering the self-portrait to be not just a faithful imitation of one's features but a representation of one's spiritual identity may have resonated (共鸣) with Leonardo.
Vezzosi, the museum director, dismissed as "baseless and senseless" the idea that the "Mona Lisa" could be a self-portrait of Leonardo. He said most researchers believe the woman may have been either a wife of the artist's sponsor, the Florentine nobleman Giuliano de Medici, or Lisa Gherardini, the wife of a rich silk merchant, Francesco del Giocondo. The traditional view is that the name "Mona Lisa" comes from the silk merchant's wife, as well as its Italian name: "La Gioconda."  
【小题1】Why does the author ask a couple of questions in the beginning?

       Honeybees are disappearing for unknown reasons around the United States．Last winter, bees disappeared from 23 percent of American beekeeping businesses．Causes of the phenomenon, however, have remained a mystery．

       Now, scientists from several universities and the United States Department of Agriculture say they have a possible explanation for the bee decline（数量下降）．It is a little known virus called Israeli acute--paralysis virus （IAPV） ．The virus kills bees．Researchers in Israel first described it in 2004 , but until now, bee experts hadn’t paid much attention to it．

       When trying to find out why the bees were disappearing, a research team at Columbia University studied bee colonies （ 群体）, some with and the others without decline．The research turned up large numbers of two types of fungi （真菌）once suspected of causing the bee decline．The research results, however, showed that the fungi were almost as common in colonies without a decline as they were in colonies with a decline．The researchers concluded that the two fungi probably weren’t the cause．

       Studies of the presence of IAPV, however, showed more interesting information．In those studies, done by a team at Pennsylvania State University in University Park, the virus showed up in 83 percent of samples from colonies with symptoms （症状）．Only five percent of samples from symptom less colonies had it．

       Scientists still don’t know whether IAPIV can single--handedly cause the bee decline．They believe that even if the virus is making colonies sick , it could have a partner in crime．It’s possible, for instance, that insects or chemicals in the environment weaken bees, making them more likely to catch IAPV．

       Scientists are still trying to figure out how IAPV came to the United States．The United States currently allows bee products to be imported from Canada, Australia, and New Zealand．If it turns out that this trade is spreading disease, the rules might eventually change．

1．According to the passage ，IAPV is a virus that ______．

       A．hasn’t attracted much attention

       B．well-known to doctors and scientist

       C．was first found by Austrian researchers

       D．is dangerous to animals and human beings

2．The underlined sentence in the fifth paragraph probably means______．

       A．the virus could also cause other damages

       B．there must be something that is the real cause

       C．IAPV is not the only cause for the bee decline

       D．the virus may be caused by the polluted environment

3．From the third and fourth paragraphs, we know researchers draw their conclusions by means of _______．

       A．calculating          B．comparing          C．examining        D．investigating

4．What still remains unknown to American scientists according to the passage?

       A．How and why to kill IAPV．

       B．How IAPV came to America．

       C．Whether bee products should be imported．

       D．How to change the rules of the bee products trade．

5．The best title for this passage would be _____．

       A．Bee Disease                                     B．How to Kill IAPV

       C．A Virus—IAPV                                  D．Two Types of Fungi