The fact that ......was discovered in 1923 by the astronomer Edwin Hubble.

1) the explanasion of he univerise

2)the universe is expanding

3)the universe , which is expanding

4) when the universe expands

答案是B. 我想知道为什么A不对?

谢谢!

of 后面是he,介词后面应该跟him 或his

而且同位语从句引导词that后面应该跟句子啊~~~~~