No one has yet succeeded in solving the of how life first began. A. biologyB. gravityC. p

问题补充：

No one has yet succeeded in solving the of how life first began.

A. biology

B. gravity

C. puzzle

D. theory

答案：

A. biology

B. gravity

(答案→)C. puzzle

D. theory

解析：可联系答.案.网客服索取。