A photoelectric surface is illuminated successively by monochromatic light of wavelength 2λ and 0.5λ. What will be the work function of the photosensitive material of the maximum kinetic energy of the photo electrons in the second case is 5 times that of the first case? In the given options h is Plank's constant and c is the speed of light.

$\frac{3hc}{4λ}$

The correct answer is Option (4) - $\frac{3hc}{4λ}$