These old pictures bring to their mind the college days they spent together life was ha

问题补充：

These old pictures bring to their mind the college days they spent together, life was hard but happy.

A. when; whose

B. which; whose

C. which; when

D. when; which

答案：

A. when; whose

B. which; whose

(答案→)C. which; when

D. when; which

解析：句意：这些旧照片使他们想起他们一起度过的大学时代,当时生活很艰苦,但是很开心。先行词days后接了两个定语从句，第一个定语从句中动词spent 后缺少宾语，因此第一空填关系代词which作宾语;第二个定语从句主语和表语都完整，所以第二空填关系副词when。故选C。