一道英语单选高考题

Question

It's said that there are plenty of hotels in the small seaside city. so there ___ be any difficulty for you to find somewhere to stay at this moment if you want to have a trip there.
A. couldn't B. mustn't C. shouldn't D. needn't
correct answer C but why?

Answer 1

B

Answer 2

C
据说在那个镇里有很多旅馆.
找到一个不会有困难.
A的意思"会要",B的意思"不应该"

Answer 3

c