The molar specific heats of an ideal gas at constant pressure and volume are denoted by \[{{C}_{p}}\] and\[{{C}_{v}}\], respectively. If \[\gamma =\frac{{{C}_{p}}}{{{C}_{v}}}\] and R is the universal gas constant, then Cy is equal to

• A. \[\frac{R}{\left( \gamma -1 \right)}\]
• B. \[\frac{\left( \gamma -1 \right)}{R}\]
• C. \[\gamma R\]     
• D. \[\frac{1+\gamma }{1-\gamma }\]