PT 64 S3 Q20

One should not play a practical joke on someone if itshows contempt for ... ...

The principle stated above, if valid, most helps to justify the reasoning in which one of the following arguments?
(A) I should not have played that practical joke on you yesterday. Even if it was not contemptuous, I should have realized that it would bring significant harm to someone.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Oct 2011 LSAT (PT 64): Logical Reasoning B