Why is the equator region the hottest part of Earth's surface?

Question

the equator is closest to the sun
the rays of the sun hit the equator region at an angle
the equator region has the widest diameter
the sun shines directly on the equator region

Answer 1

The reason the equator region is the hottest part of Earth's surface is that the sun shines directly on the equator region.

At the equator, sunlight strikes the Earth more directly than at higher latitudes, where the sunlight hits at a steeper angle. This results in more intense solar radiation per unit area, making the equatorial region warmer. The other options you provided either contain inaccuracies (e.g., the equator is not "closest" to the sun in terms of distance from the center of the Earth) or misunderstand how sunlight interacts with the Earth's surface.