When you're trying to persuade (To convince) someone yes you want to compare and contrast but when you need SUPPORT for AN ARGUMENT you need EVIDENCE.
A. The Professor
Hope you get it right.
In the short story "The Lottery," the lottery is drawn from a black box.
They used many boxes prior to the lottery in the story, but they were shabby and got destroyed, so they got a new box which was black of color.