The point S is monochromatic source of light emitting light of wavelength λ. At the point P at a distance x from the mirror as shown in the figure, interference takes place between two light rays one directly coming from source S and another after reflection from the mirror such that a maxima is formed. The value of x may be :
(a) 120 λ
(b) 125 λ
(c) 62.5 λ
(d) 187.5 λ
