解除尿路梗阻的方法，下列哪项首选（）

A.留置导尿

B.膀胱造瘘

C.肾造瘘或经皮肾穿刺造瘘

D.输尿管皮肤造瘘

E.查清病因，解除原发病

Which of the following methods is used to increase the number of processes sharing the CPU？

A． Interrupt

B． Scheduler

C． Swapping

D． Working Set