A cyclic process is graphed as shown - Heat supplied in one cycle -

Question

$(a)\;2 \pi \rho_{0} V_{0}\qquad(b)\;-2 \pi \rho_{0} V_{0}\qquad(c)\;\large\frac{ \pi} {2} \rho_{0} V_{0}\qquad(d)\;-\large\frac{ \pi} {2} \rho_{0} V_{0}$