User blog comment:12th Supernova/Chat Fights: The "Official" Rules/@comment-972068-20131117005841/@comment-972068-20131117201550

Why should I question an apple? I know why an apple is delicious. Because it's an apple. It's one of the few times a basic answer is acceptable.

If you want to be more scientific, our tongue has a number of nerves in it called "taste buds", and when they react positively, we enjoy the taste of the food we're consuming. Apples give a positive reaction to this, so we naturally enjoy apples.