TTGWD6-41

Q41:

Scientists have dated sharp-edged flakes of stone found in the fine-grained sediments of a dry riverbed in the Afar region of Ethiopia to between 2.52 and 2.60 million years ago, pushing back by more than 150,000 years the earliest date when it is known that humans made stone tools.

1. when it is known that humans made
2. at which it is known that humans had made
3. at which humans are known to have made
4. that humans are known to be making

    E.   of humans who were known to make

选哪个啊?我看看个个都有毛病:

A:date 后定语从句不用when的.

B:at 某个时间点后不应该用完成时,至少得换成since啊.

C:同上

D: be making 看上去极不爽

E:改变了句意,原句说"人类使用石器的时间往前推了",改后变成"(使用石器的)人的时间往前推了"

请大家点拨一下,谢谢了!

vote for E

挣扎了下,还是选E吧

可是这句里date其实只是指某个大致的时期而已．Ａ有没有商量的余地呢？

TTGWD该题答案就是A,但TestMagic Forum上绝大多数选C(尽管没有十分强有力的证据).

还请高手们站出来说两句吧!