Explanation:
This answer provides correct initialization parameters to define three archive locations.
Incorrect Answers:
1: For three archive locations LOG_ARCHIVE_DEST parameter will be wrong to use: it works only for one or two locations (in conjunction with LOG_ARCHIVE_DUPLEX_DEST parameter).
3: LOG_ARCHIVE_DEST_0 parameter is wrong in this sequence of initialization parameters.
4: LOG_ARCHIVE_DEST, LOG_ARCHIVE_DUPLEX_DEST parameters work good to define no more than two archive locations, not three.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 585-591
Chapter 12: Overview of Backup and Recovery

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