The victim had been dead the morning of Feb.25.A. onB. inC. sinceD. by

问题补充：

The victim had been dead the morning of Feb.25.

A. on

B. in

C. since

D. by

答案：

A. on

B. in

C. since

(答案→)D. by

解析：在表示时间时，on表示在具体某一天；in表示在一个时间范围；since后接时间点，表示自从……以来；by后接时间点，表示到……为止。句意：被害人在二月二十五日早晨止，已经死了。结合语境可知选Ｄ。