The correct option is D All of these
For an ideal gas internal energy is only a function of temperature. U=f(T)
Here, given gas is non - ideal in nature.
So, internal energy is a function of any two of the thermodynamic variables P,V and T.
U=f(P,V) or U=f(T,V) or U=f(T,P)
∴ Internal energy of non - ideal gas depends upon Temperature, Pressure and volume.
Thus, option (d) is the correct answer.