If the equilibrium constant for the reaction,$H_{2(g)} + I_{2(g)} \rightleftharpoons 2 HI_{(g)}$ is $K$,what is the equilibrium constant of $HI_{(g)} \rightleftharpoons \frac{1}{2} H_{2(g)} + \frac{1}{2} I_{2(g)}$?

• A
  $\frac{1}{K}$
• B
  $\sqrt{K}$
• C
  $K$
• D
  $\frac{1}{\sqrt{K}}$