The correct answer is A. See this link:
Adding a WebLogic Managed Server to the Domain.
Actually you don't technically NEED to use the console. You could always directly hack on the config.xml, but this is frowned upon by BEA.
For a list of the Admin command line parameters, see this link:
WebLogic Server Administration Command Reference.
[ December 15, 2002: Message edited by: Chris Mathews ]