In a young’s experiment, two coherent sources are placed 0.9 mm apart and the fringes are observed 1 m away. If it produces the second dark fringe at a distance of 1 mm from the central fringe, the wavelength of monochromatic light used would be
(A) 60 x 10-4cm
(B) 10 x 10-4 cm
(C)10 x 10-5cm
(D) 6 x 10-5cm
