35.　　 _electricity plays such an important role in our daily life?

A. Why was it that　 　B. Why is it that 　　C. Why is it what 　　D. Why it is that

34. The singer hasn’t performed in public for over 5 years. _____, she is very popular with young people.

A. But　　　　　　 　 B. still　　　　　　　 　 C. Otherwise　　　　　　 D. Therefore

33. _____on the top of the mountain is an ancient tower dating back to hundreds of years ago.

A. To stand　　 B. Having stood　　 C. Standing　　　 D. Stand

32. Ten minutes earlier ______ we could have avoided the accident.

A. or　　　　　 B. but　　　　　 C. so　　　　　 D. and