The scientists were trying to look for all possible as to where this species came from.A.

发布时间：2020-08-17 04:03:23

The scientists were trying to look for all possible      as to where this species came from.
A. signals
B. marks
C. clues
D. spots

网友回答

A. signals
B. marks
(答案→)C. clues
D. spots
解析：句意，科学家们正在努力寻找一切关于人类从哪里来的线索。Signals信号marks痕迹clues线索spots地点，根据题意，故选C。
以上问题属网友观点，不代表本站立场，仅供参考！