Here's a problem to solve: The nearest star to the Sun is described as being 4.3 light-years away. Which statement explains why the light-year unit of measure is used in this description?

Among the 4 following options, which is the correct answer?

- A: The distance is extremely large.
 
- B: The distance is a rough estimate.
 
- C: Only light can travel between stars.
 
- D: Light signals were timed reflecting from the star.
 