Explanation:
The correct response is keyword CANCEL. Without archived redo log file with sequence number 45 you cannot continue recovery. At this point you should stop recovery with CANCEL command and open database resetting logs. Incorrect Answer:
1: Typing the keyword AUTO you force Oracle to continue recovery, but it will fail with archived redo log with sequence 45 missing.
3: Pressing the Enter or Return key you also tells Oracle to continue recovery for redo log 45.
4: Without redo log 45 you cannot continue recovery process with redo log file 46.
Reference:
OCP Oracle 9i Database: Fundamentals II Exam Guide, Rama Velpuri, p. 336-337
Chapter 14: User-Managed Incomplete Recovery

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