C. Maintaining an objective tone
To address something with civility means it should be addressed in a polite, respectful manner. To do this, one must certainly maintain an objective tone because to address something subjectively (the opposite of objectively) will typically employ a defensive tone which can lead to bias (or a tone interpreted as bias). And, when constructing an argumentative paper, it is important to be free of bias, so readers feel you are addressing all sides fairly, which is vital in argumentative writing.
