Star X is larger than star Y. Star Y is larger than star X. Star X reflects the Sun’s light better than star Y. Star Y reflects the Sun’s light better than star X.
I gave my students this multiple choice question: An astronomer is studying two stars that are the same distance from Earth. Star X appears brighter than star Y. Which statement best explains this observation?

Only one answer is correct among these 4 choices:
- Star X is larger than star Y.
- Star Y is larger than star X.
- Star X reflects the Sun’s light better than star Y.
- Star Y reflects the Sun’s light better than star X.

Could you tell me which one is correct?

Star X is larger than star Y.