The Internet is a wonderful discovery, ___of great significance to people’s lives.

A．as is I think.

B．which think it is

C．which I think is

D．as I think

下列标志物中为AMI早期标志物的是（）

A.AST

B.LD

C.肌红蛋白

D.CK-MB

E.肌钙蛋白