Consider the following equilibrium reaction in gaseous state at $\mathrm{T}(\mathrm{K})$. $\mathrm{A}+2 \mathrm{~B} \rightleftharpoons 2 \mathrm{C}+\mathrm{D}$ The initial concentration of $B$ is 1.5 times that of $A$. At equilibrium, the concentrations of A and B are equal. The equilibrium constant for the reaction is

• A

  $6$
• B

  $16$
• C

  $12$
• Correct answer
  D

  $4$

Hence, the correct answer is option: 'D'.