heating the pan heating the soup heating the spoon heating the stove burner
I gave my students this multiple choice question: A pan of soup is being heated on an electric stove. A metal spoon is used to occasionally stir the soup. Which of the following is an example of heat being transferred by convection?

Only one answer is correct among these 4 choices:
- heating the pan
- heating the soup
- heating the spoon
- heating the stove burner

Could you tell me which one is correct?

heating the soup