Two long current-carrying thin wires,both with current $I$,are held by insulating threads of length $L$ and are in equilibrium as shown in the figure,with threads making an angle $\theta$ with the vertical. If the wires have mass $\lambda$ per unit length,then the value of current $I$ is ($g =$ gravitational acceleration).

• A
  $2 \sin \theta \sqrt{\frac{\pi \lambda g L}{\mu_0 \cos \theta}}$
• B
  $2 \sqrt{\frac{\pi g L}{\mu_0} \tan \theta}$
• C
  $\sqrt{\frac{\pi \lambda g L}{\mu_0} \tan \theta}$
• D
  $\sin \theta \sqrt{\frac{\pi \lambda g L}{\mu_0 \cos \theta}}$