Explanation:
To identify this situation you need to check alert log file, it will be message: "CHECKPOINT NOT COMPLETE".
Incorrect Answers:

1: V$SESSION_WAIT view is used to show list the resources or events for which active sessions are waiting, where WAIT_TIME = 0 for current events.
3: V$SYSSTAT view contains general statistics for the instance by name.
4: V$SYSTEM_EVENT view is used to show total waits for an event.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 902. Chapter 19: Tuning Disk utilization

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