Red light is used in railway signals for “stop”. The reason behind using red light for this purpose is ­

a) Red light have always been used as a signal of danger.

b) The wavelength of red light is maximum in visible light spectrum and hence dispersion is minimum.

c) The wavelength of red light is minimum in visible light spectrum and hence dispersion is minimum.

d) The wavelength of red light is maximum in visible light spectrum and hence diffraction is minimum.

Ans – [B]