A diatomic ideal gas is heated at constant volume until the pressure is doubled and again heated at constant pressure until the volume is doubled. The average molar heat capacity for the whole process is

• A. \[\frac{13R}{6}\]          
• B. \[\frac{19R}{6}\]
• C. \[\frac{23R}{6}\]          
• D. \[\frac{17R}{6}\]