I don't remember how many years ago ___ that people began to grow_英语解答

I don't remember how many years ago ___ that people began to grow crops.
A.it was when B.was it that C.it was that D.was it when

人气：287 ℃　时间：2019-12-01 08:16:10

解答

C
这是同位语强调句,我不清楚那些人多少年前开始种庄稼.
强调是那些人种庄稼,而不是别人.