单项选择题

A. The drop disk operation is still proceeding and you cannot yet run the undrop disks operation.
B. The drop disk operation is complete and you can run the undrop disks command if needed.
C. The drop disk operation is complete and you cannot run the undrop disk command.
D. The query will fail since there is not a V$ASM_OPERATION view available in an ASM instance. 
E. None of the above is true.