The sentence can be completed as follows:

"Word came that the army stationed in the city would give up and abandon it."

In this sentence, "that" is used to introduce the clause providing additional information about the word that was received.

Word came ______ the army stationed in the city would give up and abandon it.

A.what

B.that

C.which

D.how

B

解析

这是一个由that引导的word的同位语从句，从句中陈述的是事实——驻扎城中的军队要放弃城池撤走，因此用that。由于谓语(came)太短，所以被提到从句之前。