At a certain location in Africa,a compass points $12^{\circ}$ West of the geographic North. The North tip of the magnetic needle of a dip circle placed in the plane of magnetic meridian points $60^{\circ}$ above the horizontal. The horizontal component of the earth's field is measured to be $0.16\, G$. The magnitude of the earth's field at the location will be

• A
  $0.23 \times 10^{-4}\, T$
• B
  $0.18 \times 10^{-4}\, T$
• C
  $0.32 \times 10^{-4}\, T$
• D
  $0.81 \times 10^{-4}\, T$