Explanation:
There are two parameters in initialization parameters file that can cause problems when starting more shared servers: PROCESSES and MTS_MAX_SERVERS.
Incorrect Answers:

3: There is no MTS_MAX_PROCESSES parameter in Oracle.
4: The MTS_MAX_DISPATCHER parameter will not cause any problems when staring more shared servers.
5: The PARALLEL_MAX_SEVERS parameter is not related directly with shared servers to cause problems.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 858-859. Chapter 18: Tuning Memory and Operating System Use

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