Maybe if I science, and not literature then, I would be able to give you more help.
A. studied
B. would study
C. had studied
D. was studying
网友回答
A. studied
B. would study
(答案→)C. had studied
D. was studying
解析：考查虚拟语气中错综时间条件句。从句与过去与过去事实相反，而主句与现在事实相反。从句中有信息词then(那时)，说明从句与过去与过去事实相反，使用had done故选C.句意，也许如果我那时学的是科学而不是文学，我现就能给你更多的帮助。