HELP~~
Which two statements about Recovery Manager (RMAN) backups are true? (Choose two.)
A.Online redo log files can be backed up.
B.Archived redo log files are backed up.
C.Only used data blocks can be backed up as backup sets.
D.Only consistent database backups can be performed.
E.RMAN backup can be taken only if the database is configured in ARCHIVELOG mode.
Answer : B, C 

麻烦哪位帮忙讲解一下这道题为什么选B,C?
使用RMAN备份时也会备份归档日志的吗? 如果数据库处于NOARCHIVELOG模式下RMAN就不能使用是吗?
先谢过了~~

------解决方案--------------------
使用RMAN备份时也会备份归档日志的吗? 
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plus archivelog 选项可以同时备份归档日志，


如果数据库处于NOARCHIVELOG模式下RMAN就不能使用是吗? 
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能啊，增量备份主要用于此。