Concept:A question tag is a short phrase added to the end of a sentence to confirm information. The tag must match the tense and polarity (positive or negative) of the main statement.Explanation:The statement "You don't smoke" is negative (using "don't"). For a negative statement, the question tag must be positive.The main verb is "smoke", so the helping verb in the tag is "do".The pronoun is "you".Thus, the correct positive tag is "do you".Answer:C. do you