The astronaut did many experiments in the spaceship,___ much help for knowing space.

题目

The astronaut did many experiments in the spaceship,___ much help for knowing space.
A which we think is B I think which is of C of which we think is D which we think are of 为啥?A不对
When the spaceship traveled above a new-looking earth appeared before us，____that_we had never seen before
Aone B the one (为什么）

答案