Which three describe a valid OGG Event Action?

Which three describe a valid OGG Event Action?

A.
Stop the process

B.
Write a checkpoint before and/or after writing the record to the trail.

C.
Run a shell command

D.
Purge old trail files

Explanation:

In reference guide, page 312, Syntax EVENTACTIONS ([STOP | ABORT |
FORCESTOP][IGNORE [TRANSACTION [INCLUDEVENT]][DISCARD][LOG [INFO |
WARNING]][REPORT][ROLLOVER][SHELL <command>][TRACE <trace file> [TRANSACTION]
[PURGE | APPEND]][CHECKPOINT [BEFORE | AFTER | BOTH]][, …])