Final answer:
The pressure gauge on a bottle containing a gas would show a lower reading if the gas in the bottle was cooled (option B). Cooling causes a decrease in a gas's pressure when its volume is constant, an effect explained by Gay-Lussac's Law.
Step-by-step explanation:
The pressure gauge on a bottle containing a gas would show a lower reading when the gas in the bottle is cooled (option B). According to Gay-Lussac's Law, which is a gas law that describes how the pressure of a gas tends to increase as the temperature increases when the volume is held constant, the reverse is also true. If a gas within a fixed volume is cooled, its pressure decreases.
Examples demonstrating this include when heated gas in a bottle is sealed and then cooled, leading to a decrease in internal pressure, and gases within carbonated beverages, which, when opened, release pressure and form bubbles as dissolved gases come out of solution.
Pressure is also influenced by gas volume and amount; compressing a gas increases pressure whereas expanding its volume decreases it, and releasing gas into a vacuum would lower the total amount of gas and therefore reduce pressure.