If $E_1, E_2$ are two events of a sample space such that $P\left(E_1\right)=\frac{1}{4}, P\left(E_2 \mid E_1\right)=\frac{1}{2}, P\left(E_1 \mid E_2\right)=\frac{1}{4}$, then $P\left(\bar{E}_1 \mid E_2\right)=$

• A

  $\frac{1}{3}$
• B

  $\frac{1}{4}$
• C

  $\frac{2}{3}$
• Correct answer
  D

  $\frac{3}{4}$

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