Interesting that the outcome of this poll, to this point, has been 50-50. (Ruling out the identified incorrect response, C.) There is no advantage either way. Once you know C is incorrect, both A and B have 50% probability of being correct (from your perspective).

The difference between this and the Monty Hall Problem that I polled several days ago, is that the teacher has no knowledge of your choice. Hence, the teacher is equally likely to reveal either of the two incorrect responses, regardless of which option you've selected so far.