42. Which of the following statements is true for one mole of ideal monatomic gases? (A) For the isobaric process, the change in the internal energy is linearly proportional to the change in the temperature. (B) For the gas undergoing the adiabatic process, the temperature of the gas remains constant. (C) For the gas undergoing the isothermal expansion, the internal energy of the gas increases. (D) For the gas undergoing the adiabatic free expansion process, the temperature of the gas drops. (E) For the gas undergoing the adiabatic free expansion process, the internal energy of the gas increases.