While he was at________college, he took part in political activities, and was soon thrown into           prison.

A．the; /

B．/; the

C．/; /

D．the; the

各种tRNA分子3'末端的最后三个核苷酸均是

A．CGA-OH

B．CAG-OH

C．AAC-OH

D．UUA-OH

E．CCA OH