Which of the following statement/statements is/are true regarding the light year?
1. Light year is a unit of distance.
2. Light is a unit of time.
3. A light year is the distance that light travels in one Earth year.
4. Light year is the measurement of light intensity.

Correct option is C

The correct answer is (c) Only 1 and 3 are correct.
Clarification of Statements: 1. Light Year as a Unit of Distance:
True: This is the primary and correct definition of a light year. It provides astronomers with a way to describe the vast distances between stars, galaxies, and other celestial objects. For example, the nearest star system, Alpha Centauri, is about 4.37 light years away from Earth, meaning light from that star takes over four years to reach us.
2. Light as a Unit of Time:
False: Light itself does not measure time. Instead, light's speed (the distance it travels in a given time) can be used in calculations that involve time, but the term "light year" specifically refers to distance, not time.
3. Distance Light Travels in One Earth Year:
True: This statement accurately describes what a light year represents. When we say a star is 10 light years away, it means the light we see from that star today actually left it 10 years ago.
4. Measurement of Light Intensity:
False: Light year does not relate to intensity. Intensity is measured in units like lumens, watts, or candela. Light year is purely a measure of distance,