There are a lot of signs          men are more likely to have heart attacks than women.

A．indicate

B．to indicate

C．indicated

D．indicating

下列氨基酸中能转化生成儿茶酚胺的是

A．天冬氨酸

B．色氨酸

C．酪氨酸

D．丙氨酸

E．蛋氨酸