40. An ideal gas undergoes a Carnot cycle. If the volume of the gas doubles during the isothermal expansion, how does the magnitude of the work done on the gas during the isothermal compression compare to the magnitude of the work done by the gas during the isothermal expansion?
(A) The work of compression is greater.
(B) The work of expansion is greater.
(C) Both are equal.
(D) It depends on the temperature ratio of the high- and low-temperature reservoirs.