It is no use arguing _______ the plan because it has been rejected.
C
argue作动词时，意为“争论;争吵;争辩”。arguefor意为“为……辩护”;arguewithsbabout/oversth指“就某事和某人争论”;argueagainst意为“据理反对;争辩……”。根据句意，应该用for。
Studentsshould_____theirowninterestsaswellasdotheirschoolwork.
Thecentraltheatrehasaseating________ofmorethan3,000people.
_______foryourlaziness，youcouldhavefinishedtheassignmentbynow.