Concept:For a fixed mass of gas, volume is directly proportional to temperature and inversely proportional to pressure: V∝PT.Explanation:When temperature is increased, gas particles gain kinetic energy and push outward more, causing the balloon volume to increase.When pressure is decreased, the external force on the balloon is reduced, allowing it to expand more easily.Thus, the volume increases when temperature is raised and pressure is lowered.Answer:C. T is increased and P is decreased