If the absolute pressure of a confined gas is constant, then the volume is:

The correct answer reflects Boyle's Law and Charles's Law principles regarding the behavior of gases under specific conditions. When the absolute pressure of a confined gas is held constant, any change in the temperature will directly affect the volume of the gas.

According to Charles's Law, which states that the volume of a gas is directly proportional to its absolute temperature when pressure is constant, an increase in temperature will cause an increase in volume, while a decrease in temperature will cause a decrease in volume. This relationship can be expressed with the formula V/T = constant, where V is the volume and T is the absolute temperature. Therefore, if the pressure is constant, the volume of the gas will change in direct proportion to its temperature.

The assertion that volume is inversely proportional to absolute temperature is not accurate in this context and contradicts Charles's Law, which is why this choice is not the right answer. Instead, it is the direct proportionality that holds true when absolute pressure remains constant. Understanding these gas laws is fundamental for dealing with thermodynamic processes in power engineering.