下面（）Oracle系统进程主要负责在一个Oracle进程失败时清理资源。

A.All_ROWS
B.Cost-basedoptimizer
C.Rule-based optimizer
D.Choose

A.NORMAL
B.ABORT
C.IMMEDIATE
D.NONE

A.ALTER SYSTEM SUSPEND
B.ALTER DATABASE SUSPEND
C.ALTER SYSTEM  QUIESCE  RESTRICTED
D.ALTER SYSTEM OFFLINE