Susan decided not to work on the program at home because she didn’t’ want her parents to know what she .
A. has done
B. had done
C. was doing
D. is doing
网友回答
A. has done
B. had done
(答案→)C. was doing
D. is doing
解析：考查动词的时态。因为主语的工作当时尚未完成，又处于过去的时间背景当中，所以采用过去进行时态。