The listener has shut down unexpectedly. You want to view the listener log file and listener trace file to find the cause of the problem. How can you view the contents of the listener log file and the listener trace file？（）

• A、 Open the file at the location specified by the BACKGROUND_DUMP_DEST parameter in the pfile.
• B、 Open the file at the location specified by the USER_DUMP_DEST parameter in the pfile.
• C、 Issue the SERVICES command at the LSNRCTL> prompt.
• D、 Issue the STATUS command at the LSNRCTL> prompt.