Of the Five Statements Below About the Specific Heat Difference

Of the five statements below about the specific heat difference C_p - C_v, chose the wrong one:

A) The specific heat difference C_p - C_v of a substance is positive or zero.
B) The specific heat difference C_p - C_v at a given absolute temperature T is proportional to T.
C) The specific heat difference C_p - C_v is zero for incompressible substances.
D) The specific heat difference C_p - C_v of an ideal gas is independent of temperature.
E) The specific heat difference C_p - C_v is proportional to isothermal compressibility.