Question

Which of the following is an appropriate unit to measure large distances across the universe? An astronomical unit A kilometer A light year A mile

Answer 1

I assume a light year. It is the distance that light travels in a year, and seems the most accurate to describe such big distances. 

Answer 2

Light year is an appropriate unit to measure large distance across the universe.

Step-by-step explanation:

Light year is the unit of length. It is used to measure large distances across the universe. It is equal to 9.46 trillion kilometers or 5.88 miles. It is equal to distance travelled by the beam of light in one year.

An astronomical unit, a kilometer and a mile are other units. Astronomical unit is used to measure the distance in solar system.

Hence, the correct option is (c) " A light year ".