Answer:
D. ...Man,if there were one time I would actually want to cheat on a test, this might be it...
Step-by-step explanation:
The only sentence that relays any form of irony is answer D. B and C are just statements that the narrator made to carry on the story. A is a piece of internal dialogue, but it is not irony and it does not bring anything humorous to the story. Therefore, the only option left is D.