Answer:
4. Warm air from the inside moving toward the cold air outside.
Explanation:
A cold draft can be defined as the process in which a current of cold air is being drawn in from the outside. Also, it involves the process in which a current of warm inside air exits or leaves a building through an opening.
This ultimately implies that, when you open the door to your house on a cold day, you would feel a cold draft as a result of the movement between the warm air from the inside moving toward the cold air outside. The warm air that were trapped inside your house would escape through the door due to a difference between the outside (cold) and inside (warm) atmospheric pressure.
Hence, a difference in temperature and atmospheric pressure between the outside and inside air usually causes a cold draft.
Additionally, air typically moves or travels from a region of high pressure to a region of lower pressure.
