Answer: D. the movement of energy by waves that travel through space
Step-by-step explanation:
There are three modes of heat transfer:
1. Conduction: This type of heat transfer happens when there is direct contact between the two object.
2. Convection: his type of heat transfer happens when there is a movement of fluid (liquid or gas) in which convection currents are produced due to the movement of hot fluid upwards and cold fluid downwards. This happens as the density of hot fluid decreases and thus it moves upwards.
3. Radiation: This type of heat transfer happens when there is direct transfer of energy through space.