Jovian planets Halley's comet Milky Way galaxy Orion's belt
I gave my students this multiple choice question: Structures in the universe are grouped into large systems, each of which are made up of smaller systems. Which of the following is the largest system of which Earth is only a very small part?

Only one answer is correct among these 4 choices:
- Jovian planets
- Halley's comet
- Milky Way galaxy
- Orion's belt

Could you tell me which one is correct?

Milky Way galaxy