John won a gold medal in the English competition really excited his family.A. ThatB. when

问题补充：

John won a gold medal in the English competition really excited his family.

A. That

B. when

C. which

D. what

答案：

(答案→)A. That

B. when

C. which

D. what

解析：考查主语从句。本题中的that引导主语从句that John won a gold medal in the English competition.在句中that不充当任何成分，只起引导和连接作用。句意：John在英语比赛中赢得了金牌这件事情让他的家人很高兴。BC两项都有疑问的意思，what要在句中充当一定的句子成分。故A正确。