单项选择题
Inyourdatabase,UNDO_RETENTIONhasbeensetto600secandUNDOtablespaceisconfiguredforRETENTIONGUARANTEE.WhichstatementregardingRETENTIONGUARANTEEistrue?()
A.Undodataisretaineduntilthenextfulldatabasebackup.
B.Nocommittedundodatawillbeoverwrittenfor10minutes.
C.Committedundodatawillbekeptforeverifnotoverwrittenwithin600seconds.
D.Guaranteesthatrequestedundoinformationareavailableuntiltheinstanceisshutdown.