Explanation:
By default, the PMON process registers service information with its local listener on the default local address of TCP/IP, port 1521. As long as the listener configuration is synchronized with the database configuration, PMON can register service information with a non default local listener or a remote listener on another node. Synchronization is simply a matter of specifying the protocol address of the listener in the listener.ora file and the location of the listener in the initialization parameter file. Incorrect Answer:
1: Dynamic service registration does not require configuration in the listener .ora file.
2: Dynamic service registration can be used not only with an Oracle9/instance.
3: If you want PMON to register with a local listener that does not use TCP/IP, port 1521, configure the LOCAL_LISTENER parameter in the initialization parameter file to locate the local listener.
Reference:
OCP Oracle 9i Database: Fundamentals II Exam Guide, Rama Velpuri, p. 61
Chapter 3: Basic Net Server-Side Configuration

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