A coil having inductance $L$ and resistance $R$ is connected to a battery of emf $\mathrm{\epsilon }$ at $t=0$. If $t_1$ and $t_2$ are the times for $90\%$ and $99\%$ completion of the current growth in the circuit, then $\frac{t_1}{t_2}$ will be

• Correct answer
  A

  $1:2$
• B

  $2:1$
• C

  $1:5$
• D

  $5:1$

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