At a place the true value of angle of dip is $60°$. If dip circle is rotated by $\mathrm{\varphi }°$ from magnetic meridian, the angle of dip is found to be ${\tan }^{-1}\left(2\right)$. Then the value of $\mathrm{\varphi }$ is

• A

  $45°$
• B

  $15°$
• C

  $60°$
• Correct answer
  D

  $30°$

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