Answer:
The ice cream and the air are at a different temperature, the air temperature being higher than the ice cream temperature.
Due to this difference, the air and ice cream will tend to reach a state of equilibrium by transferring energy in the form of heat, which flows from the system with a higher temperature to the system with a lower temperature.
So the hot air will transfer heat to the ice cream, which will increase its temperature and will make it liquid, so the ice cream will eventually melt.
