Is this your uncle?
Yes, it is.
No, it isn't.
Yes, he is.
No, he isn't.
Are all answers correct?
Yes, all are correct.
=)
No, not all of the answers would be correct. The correct answer to the question "Is this your uncle?" would depend on the specific situation or context.
If the person being referred to is indeed your uncle, then the answers "Yes, it is" or "Yes, he is" would be correct.
If the person being referred to is not your uncle, then the answers "No, it isn't" or "No, he isn't" would be correct.
So, it is important to evaluate the information given and determine whether it aligns with the question being asked in order to provide the correct answer.