Welcome to our charity showIt will be held the night of May 4th．A. onB. inC. atD. /

问题补充：

Welcome to our charity show．It will be held the night of May 4th．

A. on

B. in

C. at

D. /

答案：

(答案→)A. on

B. in

C. at

D. /

解析：根据语境可知此句的含义是这个活动将在五月四号的晚上举行。确指某天的晚上的时候要用介词on。故选A。