Question

visible light travels in a straight line until something gets in the way
refraction occurs when light slows down as it travels through different mediums. mediums are things like water, diamonds, glass, and air. when light slows down it appears distorted.
the index of refraction is a scale that gives us a value of how much light will slow down. light travels fastest through a vacuum and slows down as it goes through different mediums. as the number value on the index of refraction increases, the speed of light decreases.
what scale is used as an indicator for how much a specific medium will distort light?
index of reflection
index of refraction
index of absorption

Explanation:

The index of refraction is a measure that indicates how much a medium will distort (or bend) light as it passes through. The index of reflection is related to how much light is reflected from a surface, not distortion. The index of absorption relates to how much light is absorbed by a medium, not distortion.

Answer:

index of refraction