What should you look at first to compute the number of undo blocks that are consumed and estimate the size of the undo tablespace needed to handle the workload on your system?

What should you look at first to compute the number of undo blocks that are consumed and
estimate the size of the undo tablespace needed to handle the workload on your system?

A.
V$TRANSACTION

B.
V$ROLLSTAT

C.
V$UNDOSTAT

D.
DBA_ROLLBACK_SEGS

E.
DBA_UNDO_EXTENTS

Explanation: