A cyclic process 1-2-3-4-1 consisting of two isobars 2 - 3 and 4 - 1, an isochor 1 - 2 and a process 3 - 4 represented by straight line on a P - V diagram, as shown in figure, involves n moles of an ideal gas. The gas temperatures at states 1, 2, 3 and 4 are $$T_1$$, $$T_2$$, $$T_3$$ and $$T_4$$ respectively. Also points 3 and 4 lie on the same isotherm. The work done by gas during the cycle is

A

$$\frac{1}{2}nR(T_2 - T_1)\left(\frac{T_2}{T_1} + \frac{T_3}{T_4} - 2\right)$$

B

$$\frac{1}{2}nR(T_3 - T_2)\left(\frac{T_3}{T_2} + \frac{T_4}{T_1} - 2\right)$$

C

$$\frac{1}{2}nR(T_2 - T_1)\left(\frac{T_3}{T_1} + \frac{T_3}{T_2} - 2\right)$$

D

Zero