— Jimmy had a lot of parties recently. — Yes that might why he didn’t do well in the test

问题补充：

— Jimmy had a lot of parties recently.

— Yes, that might why he didn’t do well in the test.

A. sum up

B. add up to

C. account for

D. count on

答案：

A. sum up

B. add up to

(答案→)C. account for

D. count on

解析：短语辨析. A.总结;B.合计达;C.说明……的原因；D.指望；依靠。句意，吉米最近参加了很多聚会。——是的，那可能说明了他这次考试不好的原因。选C。