A . Undo data becomes obsolete after 1，000 seconds.
B . Undo data gets refreshed after 1，000 seconds.
C . Undo data will be stored permanently after 1，000 seconds.
D . Committed undo data would be retained for 1，000 seconds if free undo space is available.
E . Undo data will be retained in the UNDOtablespacefor 1，000 seconds， then it gets movedmovedto the TEMPORARYtablespaceto provide read consistency.