Cameron Observes a Campus Police Officer Writing a Parking Ticket

Cameron observes a campus police officer writing a parking ticket for a car that is illegally parked.Even though it is not Cameron's car,he believes the officer should not issue the ticket because the no parking sign is hidden by a bush.Anyone parking their car would be highly unlikely to see the sign.Cameron says to the officer,"That's an unfair bunch of crap.No way this guy could have seen the no parking sign.The university is just a money-grubbing organization that does not give a damn about students." The officer is not amused or enlightened by Cameron's comments and tells him to back off.Cameron says,"Back off yourself." Cameron has committed:

A) interference with public duties.
B) obstruction or retaliation.
C) false report to a peace officer.
D) no offense because Cameron's comments are protected by the First Amendment.