I have been trying to advise them not to act that way, but my advice had no _________on them.

A．impression

B．advantage

C．influence

D．affect

化学本质为核糖核酸的酶是（）

A.DNA聚合酶

B.核酶

C.RNA聚合酶

D.限制性内切核酸酶

E.DNA连接酶