They have no idea at all___.

A．where he has gone

B．where did he go

C．which place he has gone

D．where has he gone

下列与乙肝慢性化有关的是（）。

A.DNA病毒

B.病毒产生前S蛋白

C.母婴传播或幼儿期感染，导致免疫耐受

D.病毒反复感染

E.L清中存在抗-HBe