After sailing for five months they arrived at they thought was the place they had been lo

问题补充：

After sailing for five months, they arrived at they thought was the place they had been looking for.

A. what

B. that

C. which

D. where

答案：

(答案→)A. what

B. that

C. which

D. where

解析： 四个选项分别表示什么、那个、哪一个和哪里，这里关系代词为thought的逻辑宾语，故选A。