Explanation:
ARCH process does not work in instance recovery itself. SMON background process just may use archived by ARCH process redo log files for recovery purposes.
Incorrect Answers:
1: ARCH process writes data to the archive log files, but it has nothing to do with instance recovery process.
2: LGWR process writes data changes into redo log files, not ARCH.
3: PMON process frees resources held by user processes.
4: CKPT process synchronizes data file header and control file.
5: DBWR background process writes dirty buffers from the buffer cache to the data files, not ARCH.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 657
Chapter 14: Database Failure and Recovery

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