Concept:A light year is a unit of distance used in astronomy.
Explanation:It is defined as the distance travelled by light in one year.
Light moves at a constant speed of about
3×108 meters per second.
In one year, light covers an enormous distance — roughly
9.461 trillion kilometers.
Since the quantity measured is a length, a light year is a unit of distance, not time or light intensity.
Thus, among the given options, the correct description is "Distance".
Light year is particularly useful for measuring vast distances between stars and galaxies.
Answer:Distance