What happens to a ray of light passing through the center of a lens

When light passes through the center of the lens then there is NO Refraction of light.

Explanation:

Center of the lens is also known as optical center and the main property of optical center is that it is the point at which the angle of incidence is always zero.

So here when light incident at that point then due to law of refraction there is no change in the direction of light or we can say that there is no refraction of light when light passes through the optical center of the lens

As we know that

since here angle of incidence is zero degree so angle of refraction is also zero degree

so there is no refraction of light when light passes through the optical center

spectral lines lyman is one set

the answer is b, have negligible mass