Gravitational lensing occurs because:
A. gravity causes light to slow down.
B. gravity curves space and light always follows the straightest possible path through space.
C. the effects of gravity are indistinguishable from the effects of glass lenses.

C. the effects of gravity are indistinguishable from the effects of glass lenses.

Explanation:

A gravitational lensing is the effect observed when light passes by a huge amount of mater that causes the light to be distorted or dip and curve resulting in the magnification of the light coming for more distant galaxies that are in similar line of sight. It is akin to a magnifying glass and aids in the study of very distant galaxies, that are not observable by current telescope technologies.

The correct answer is B)

gravity curves space and light always follows the straightest possible path through space.

Explanation:

A gravitational lens can occur when a large volume of matter, like a cluster of galaxies, creates a gravitational field that distorts and magnifies the light from distant galaxies that are behind it but in the same line of sight.

The effect is like looking at the distant galaxies through a giant magnifying glass. Only in this case, the giant magnifying glass causing the distortion is the gravitational field from the cluster of galaxies in the same line of sight.

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