Two coherent sources separated by distance d are radiating in phase having wavelength $\lambda \text{. }$ A detector moves in a big circle around the two sources in the plane of the two sources. The angular position of n = 4 interference maxima is given as

• A

  ${\sin }^{-1}\frac{\mathrm{n\lambda }}{\mathrm{d}}$

• B

  ${\cos }^{-1}\frac{4\mathrm{\lambda }}{\mathrm{d}}$

• C

  ${\tan }^{-1}\frac{\mathrm{d}}{4\mathrm{\lambda }}$

• D

  ${\cos }^{-1}\frac{\mathrm{\lambda }}{4\mathrm{d}}$