When light passes through a slit whose size is comparable to the wavelength of the light, the screen shows which of the following
a. bright spots due to constructive interference of light waves, and dark spots due to destructive interference of light waves.
b. bright and dark spots due to destructive interference of light waves.
c. nothing.
d. bright spots due to destructive interference of light waves, and dark spots due to constructive interference of light waves.
e. bright and dark spots due to constructive interference of light waves.
f. none of the above.

A. bright spots due to constructive interference of light waves, and dark spots due to destructive interference of light waves.

Explanation:

When two waves superimpose at a point with same phase conditions then it will give maximum resultant amplitude.

This condition is known as constructive interference and hence we got bright spot of the screen.

Now if two waves superimpose in opposite phase condition then it will given least intensity on the screen.

This condition is known as destructive interference and hence we got dark spot on the screen.

So here correct answer will be

A. bright spots due to constructive interference of light waves, and dark spots due to destructive interference of light waves.