Answer:
Explanation:
The image shows the relative sizes of the four imaginary planets A, B, C, and D. Thus, you must reason based only in the size difference of the planets, assuming other conditions are the same.
The atmosphere is formed by gases which are substances with low densities.
The gases, and any object, are attracted to the planets by the force of gravity.
The force of gravity is directly related to the mass of the planet: the bigger the planet, you must assume, the more massive it is, and the greater the force on gravity that it exerts on the objects near its surface.
Thus, since the planet A is the smallest of the four imaginary planets, you must conclude that it would retain the gases with less strength and thus it would likely have the thinnest atmosphere.
