The answer would be A. cheating, because you always have to show your work, so the teachers know you understand it, and didn't just take it from some website or book without fully understanding it. Hope this helps, and good luck!
A. Cheating Because if you take information of a cite and you don't give it credit then you are taking information that doesn't belong to you and your taking it and getting the credit for it in your work so that said you are cheating.
