--Will the new iphone cost a lot?--I ___ think so.Apple's products are usually expensive.(A).shouldn't(B).needn't(C).would(D).must 为什么?

问题描述:

--Will the new iphone cost a lot?--I ___ think so.Apple's products are usually expensive.
(A).shouldn't(B).needn't(C).would(D).must 为什么?