There ought to be an exam this week, ________ ?

There ought to be an exam this week, ________ ?

A.oughtn't it

B.isn't it

C.oughtn't there

D.isn't there

答案及解析： C

解析：

陈述部分There be句式带有情态动词，变疑问时把情态动词放在there之前，故选C．