Which events would you consider from the output for further investigation?

You want to review a summary of all the wait events in an instance since it started over a month ago.
You issued the following query:
SQL>SELECT event, total_waits, time_waited, average_wait
FROM V$SYSTEM_EVENT
ORDER BY time_waited DESC;
View the Exhibit and examine a portion of the output from the above query.

Which events would you consider from the output for further investigation? (Choose all that apply.)

A.
log file sync

B.
rdbms ipc message

C.
SQL*Net message from client

D.
log file switch (checkpoint incomplete)