For an ideal gas, the specific heat at constant pressure Cp is greater than the specific heat at constant volume C, because the A. Gas does work on its environment when its pressure remains constant while its temperature is increased. B. Heat input per degree increase in temperature is the same in processes for which either the pressure or the volume is kept constant. C. Pressure of the gas remains constant when its temperature remains constant. D. Increase in the gas's internal energy is greater when the pressure remains constant than when the volume remains constant E. Heat needed is greater when the volume remains constant than when the pressure remains constant.