They are similar in shape. They rotate in the same direction. They contain the same number of stars. They have similar elements.
I gave my students this multiple choice question: What do the Milky Way Galaxy and other galaxies in the universe have in common?

Only one answer is correct among these 4 choices:
- They are similar in shape.
- They rotate in the same direction.
- They contain the same number of stars.
- They have similar elements.

Could you tell me which one is correct?

They have similar elements.