避孕方法中，失败率较高的是（）

A.宫内节育器

B.VI服避孕药

C.安全期避孕

D. * * 隔膜

E.避孕套

When the government reallocates spending based upon a decision to promote new and developing industries, this would be categorized as:

A. a structural change.
B. monetary policy.
C. a cyclical change.