According to Charles's Law, what happens to pressure when volume is increased?

In the context of Charles's Law, which states that the volume of a gas is directly proportional to its temperature when pressure is held constant, it's important to clarify the relationship between volume and pressure specifically.

When the volume of a gas increases while temperature remains constant, the pressure exerted by the gas decreases. This occurs because a greater volume allows gas molecules to move farther apart, resulting in fewer collisions with the walls of the container, which is what generates pressure. Therefore, an increase in volume leads to a decrease in pressure, explaining why the correct answer indicates a decrease in pressure.

The other options do not align with this fundamental principle of gas behavior in thermodynamics. For instance, if pressure were to remain constant, the volume would need to increase in tandem with a temperature increase, not just a volume change. Meanwhile, increased pressure would imply that the volume is either not changing or is being reduced, which contradicts the premise of an increased volume. Fluctuating pressure is also not a consistent result of a change in volume under the conditions described by Charles's Law.