题目内容：

he wants to buy a new pair
His trousers are worn out.He wants to buy a new __
A.one B.pair C.trousers

优质解答

B trousers本身是一个复数的概念,所以不能选A.另一方面,由于有a new,限定了这里要填的应该是一个单数,所以也不能选C.应该选B