阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。

　　While income worry is a rather common problem of the aged,loneliness is another problem that aged parents may face．Of all the reasons that explain their loneliness,a large geographical distance between parents and their children is the major one．This phenomenon（现象）is commonly known as“Empty Nest Syndrome”（空巢综合症）．

　　In order to seek better chances outside their countries,many young people have gone abroad,leaving their parents behind with no clear idea of when they will return home．Their parents spend countless lonely days and nights,taking care of themselves,in the hope that someday their children will come back to stay with them．The fact that most of these young people have gone to Europeanized or Americanized societies makes it unlikely that they will hold as tightly to the value of duty as they would have if they had not left their countries．Whatever the case,it has been noted that the values they hold do not necessarily match what they actually do．This geographical and cultural distance also prevents the grown up children from providing response（回应）in time for their aged parents living by themselves．

　　The situation in which grown-up children live far away from their aged parents has been described as“distant parent phenomenon”,which is common both in devel-oped countries and in developing countries．Our society has not yet been well prepared for“Empty Nest Syndrome”．

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