The volume - temperature graphs of a given mass of an ideal gas at constant pressures are shown below. What is the correct order of pressures?

Question

$(a)\; P_1 > P_3 > P_2$

$(b)\; P_1 > P_2 > P_3$

$(c)\; P_2 > P_3 > P_1$ 

$(d)\; P_2 > P_1 > P_3$