prep 07 - 2 - 69/ 19号考了, 请NN们帮忙看下

龍之哀伤

Sixty-five million years ago, according to some scientists, an asteroid bigger than Mount Everest slammed into North America, which, causing plant and animal extinctions, marks the end of the geologic era known as the Cretaceous Period.
(A) which, causing plant and animal extinctions, marks
(B) which caused the plant and animal extinctions marking
(C) and causing plant and animal extinctions that mark
(D) an event that caused plant and animal extinctions, and it marks
(E) an event that caused the plant and animal extinctions that mark √

想请问下NN们, 这题的意思应该是event marks吧, E里面变成了extinctions that mark
还有, PREP的解释说D里面的", AND IT MAKRS" run-on" 这个咋run-on啦?

谢谢大家

ak007

帮你顶一下，不是牛牛，说说我自己的想法啊

D项(D) an asteroid bigger than Mount Everest slammed into North America, 同位语, and it marks 中的it就指代 asteroid了，就指代错误了啊~


“这题的意思应该是event marks吧, E里面变成了extinctions that mark”
这个我也不清楚。我认为是extinctions  mark the end of the geologic era known as the Cretaceous Period



继续求解~

nemiah

这种两个that定语从句是不是不太好啊?但其他答案也都不好。