常见输血后肝炎是哪型病毒引起的（）

A.甲型肝炎病毒

B.乙型肝炎病毒

C.丙型肝炎病毒

D.丁型肝炎病毒

E.戊型肝炎病毒

—Has Ham started out? He said he would join in the party.

—He ____. He is a man who always keeps his word.

A．must have left

B．need have left

C．should have left

D．could have left