问题补充：
Family fights are the things I feel upset.
A. about which
B. of which
C. in which
D. on which
答案：
(答案→)A. about which
B. of which
C. in which
D. on which
解析：考查定语从句：介词+which引导定语从句，修饰the things，介词的选择是根据后面的be upset的搭配，用about，对…难过。句意：家庭争吵是我感到难过的事情。选A。
