[求助]GWD1-Q30

GWD1-Q30:

The ancient Anasazi harvested such native desert vegetation as the purple-flowered bee plant, what they now commonly call wild spinach in northern Arizona and other parts of the southwestern United States.

A.      what they now commonly call

B.      a plant that they now commonly call

C.      now commonly called

D.      and is mow commonly called

E.       which it is now commonly called

就是不明白....为什么C对,其它都错哪了?麻烦哪位NN帮解答一下.......

刚才看了其他贴了,明白了,自己回一下,C省略了which is,最简洁

第一次来语法专区,没有意识到先去搜索...不好意思.....