the distance between Earth and its Moon the distance between Jupiter and the Sun the distance between the Milky Way and the nearest galaxy the distance between the Sun and the center of the Milky Way
I gave my students this multiple choice question: Which distance is the smallest for which it is most practical to use the light-year as a unit of measurement?

Only one answer is correct among these 4 choices:
- the distance between Earth and its Moon
- the distance between Jupiter and the Sun
- the distance between the Milky Way and the nearest galaxy
- the distance between the Sun and the center of the Milky Way

Could you tell me which one is correct?

the distance between the Sun and the center of the Milky Way