多项选择题
You plan to take a closed database backup using operating system commands. Which three SHUTDOWN options are appropriate for this type of backup？（）
A.ABORT B.NORMAL C.IMMEDIATE D.TRANSACTIONAL
单项选择题 WhichmodifierisusedtochangelistenerparametersintheListenerControlutilityenvironment？（）
单项选择题 WhichphrasebestdescribesRMANmultiplexedbackupsets？（）
多项选择题 WhichthreefeaturesareprovidedbyOracleNetServices？（）
