PIMSO 2023 - Science - Primary 5 - National Round Question 17

Ovens can cook food even if the food is NOT in direct contact with the food being cooked. This is because the air inside the oven transfers heat to the food.
This illustrates what kind of heat transfer?

By Vyacheslav Argenberg, http://www.vascoplanet.com/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=104997108