• Question tags are short questions added to the end of a statement to turn it into a confirmation question.
• The question tag uses the auxiliary verb (or a form of "be") from the main clause, negated if the main clause is positive, and vice versa.
• In the sentence "You went to the market yesterday," the main clause is positive ("went").
• Therefore, the question tag should use the auxiliary verb "did" in its negative form, which is "didn't."

The other options are incorrect because:

• isn't you - This uses the wrong form of "be" (be + not) and an incorrect pronoun ("you" should be "it" in this case).
• doesn't you - This also uses the wrong form of "be" and an incorrect pronoun.