Monochromatic light of wavelength λ in air is incident normally on a thin film of refractive index n. The film is surrounded by air. The intensity of the reflected light is a minimum. What is a possible thickness of the film?

A.     \(\frac{\lambda }{{4n}}\)

B.     \(\frac{{3\lambda }}{{4n}}\)

C.     \(\frac{\lambda }{n}\)

D.     \(\frac{{5\lambda }}{{4n}}\)

C