The Relation PV = NRT Holds for All Ideal Gases $\infty$

The relation PV = nRT holds for all ideal gases.The additional relation PV ^- holds for an adiabatic process.The figure below shows two curves: one is an adiabat and one is an isotherm.Each starts at the same pressure and volume.Which statement is correct? (Note: " $\infty$ " means "is proportional to". )

A) Isotherm: $p \propto \frac { 1 } { V }$ ;Adiabat: $p \propto \frac { 1 } { V }$ : A is both an isotherm and an adiabat.
B) Isotherm: $p \propto \frac { 1 } { V ^ { \gamma } }$ ;Adiabat: $p \propto \frac { 1 } { V }$ : B is an isotherm,A is an adiabat.
C) Isotherm: $p \propto \frac { 1 } { V }$ ;Adiabat: $p \propto \frac { 1 } { V ^ { \gamma } }$ : A is an isotherm,B is an adiabat.
D) Isotherm: $p \propto \frac { 1 } { V ^ { \gamma } }$ ;Adiabat: $$p \propto \frac { 1 } { V ^ { \gamma } }$$ :B is both an isotherm and an adiabat.
E) cannot answer without additional information about the starting temperature.