They are similar in shape. They rotate in the same direction. They contain the same number of stars. They have similar elements.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: What do the Milky Way Galaxy and other galaxies in the universe have in common?
Possibilities:
- They are similar in shape.
- They rotate in the same direction.
- They contain the same number of stars.
- They have similar elements.

They have similar elements.