What is true if you want to switch undo tablespaces from the current one, called UNDO1, to a new one called UNDO2?()
A.
It is NOT possible to switch unless no active transaction exist in UNDO1.
B.
It is possible to switch to UNDO2; but current active transactions will abort.
C.
It is possible to switch to UNDO2; current active transactions will be automatically migrated to UNDO2.
D.
It is possible to switch to UNDO2; only current active transactions will continue to execute inside UNDO1.