Type of Thermodynamic Processes: the Figure Shows a PV Diagram

Type of thermodynamic processes: The figure shows a pV diagram for 0.95 mol of gas that undergoes the process 1 → 2. The gas then undergoes an isochoric heating from point 2 until the pressure is restored to the value it had at point 1. What is the final temperature of the gas? The ideal gas constant is R = 8.314 J/mol ∙ K = 0.0821 L ∙ atm/mol ∙ K.

A) -160°C
B) 15°C
C) 390°C
D) 120°C