Setting redundant components in subsystem to handle with the risks brought by the defaults of original components,what kind of risk response strategy is this?（）

A.Risk avoidance

B.Risk acceptance

C.Risk mitigation

D.Contingency plan

可用于肾癌栓塞的方法有（）

A.明胶海绵栓塞法

B.碘化油栓塞法

C.不锈钢圈栓塞法

D.无水酒精栓塞法

E.联合栓塞法