OCP CBT Question 676

Please solve the following question.

You are a DBA and need to terminate a user session that is causing contention and blocking other sessions. You have identified the session with SID 123 and SERIAL# 456 from `V$SESSION`. Which command should you execute to terminate this session?

V$SESSION Output Example
SID    SERIAL#  USERNAME    STATUS    STATE        EVENT
------ -------- ----------- --------- ------------ --------------------------------
123    456      HR          ACTIVE    WAITING      enq: TX - row lock contention

ALTER SYSTEM DISCONNECT SESSION '123,456' IMMEDIATE;

ALTER SYSTEM KILL SESSION '123,456';

ALTER SYSTEM TERMINATE SESSION '123,456';

ALTER SYSTEM UNLOCK SESSION '123,456';