A coil having effective area $A$, is held with its plane normal to magnetic field of induction $\mathrm{B}$. The magnetic induction is quickly reduced by $25 \%$ of its initial value in 2 second. Then the e.m.f. induced across the coil will be

• A

  $\frac{\mathrm{AB}}{4}$
• B

  $\frac{\mathrm{AB}}{2}$
• C

  $\frac{\mathrm{3AB}}{4}$
• Correct answer
  D

  $\frac{\mathrm{3AB}}{8}$

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