Which command forces a running Extract to close the current trial and start writing to the next trial sequence number?

Which command forces a running Extract to close the current trial and start writing to the next trial
sequence number?

A.
ALTER EXTTRAIL <trail name>, NEXTSEQNO

B.
ALTER EXTTRAIL <trail name>, ROLLOVER

C.
SEND EXTRACT <group>, ETROLLOVER

D.
SEND EXTRACT <group>, ROLLOVER

Explanation:
Reference :
http://download.oracle.com/docs/cd/E15881_01/doc.104/gg_wux_ref_v104.pdf