So far the number of deaths caused by the earthquake in Chile has _________750.

A．appealed to

B．added to

C．amounted to

D．devoted to

静脉注射生物制剂→共同使用针管(只换针头)→注射器污染HBV→HBV感染→乙型肝炎发作。这一因果连接方式称为

A．单因单果 B．多因单果 C．单因多果 D．多因多果 E．直接/间接病因