Much to the couple’s comfort their income is now double it was five years ago.A. thatB.

问题补充：

Much to the couple’s comfort, their income is now double it was five years ago.

A. that

B. than

C. which

D. what

答案：

A. that

B. than

C. which

(答案→)D. what

解析： 考查宾语从句。is now double是谓语部分，所以后面跟的是宾语从句，宾从 it was five years ago缺少was的表语，所以用what引导。选D。