To determine which model shows the part of Earth's surface that would heat up the least due to sunlight striking at different angles, you should consider the angle at which sunlight hits the surface.
Generally, sunlight striking the Earth's surface at a lower angle (more oblique) distributes the energy over a larger area, resulting in less intense heating. In contrast, sunlight hitting the surface at a steeper angle (more directly) concentrates the energy over a smaller area, leading to more intense heating.
Without seeing the specific models, look for the model where the sunlight strikes the Earth's surface at the least direct angle. This will represent the area that would heat up the least. Based on that reasoning, choose the model that depicts the most oblique angle of sunlight.
If you have the option letters (A, B, C) associated with specific orientations or angles, select the one that is most oblique to answer your question accurately.