Explanation:
A DBA can use the initialization parameter LOG_ARCHIVE_DEST_STATE_n set to value DEFER to disable one of the current archive destinations. The SQL query below shows current state of archive destinations. SQL> select name || ' ' || value from v$parameter where2 UPPER (name) like 'LOG_ARCHIVE_DEST_STATE%'; NAME||''||VALUE
log_archive_dest_state_1 enable
log_archive_dest_state_2 enable
log_archive_dest_state_3 enable
log_archive_dest_state_4 enable
log_archive_dest_state_5 enable
log_archive_dest_state_6 enable
log_archive_dest_state_7 enable
log_archive_dest_state_8 enable
log_archive_dest_state_9 enable
log_archive_dest_state_10 enable
Incorrect Answers:
1: ALTER SESSION SET ARCHIVE_LOG_DEST=DEFER command will not disable one of the current archive destinations because this parameter cannot be changed with option DEFER.
2: Deleting the archive destination dictionary at the operating system level will not disable one of the current archive destinations.
4: It is possible to disable archive destinations with DEFER option.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 583-585
Chapter 12: Overview of Backup and Recovery

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