Explanation:
When the LARGE_POOL_SIZE parameter is set to a valid value Oracle allocates memory for the large pool during instance startup. If value is wrong, large pool will not be allocated.
Incorrect Answers:

1: There is no correlation with PARALLEL_AUTOMATIC_TUNNING parameter and large pool. This parameter enables intelligent defaults for parallel execution parameters.
2: Large pool can be used with the Dedicated Server mode also, not only with the Multithreaded Server.
4: The large pool is optional structure of memory and does not have a default value.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 857-858. Chapter 18: Tuning Memory and Operating System Use

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