clouds of hot gas large numbers of stars high energy compounds extremely reflective ice particles
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: The Milky Way Galaxy is visible as a bright region in the night sky. Modern telescopic observation has made it possible to discover that the brightness of the Milky Way Galaxy is due primarily to which structure?
Possibilities:
- clouds of hot gas
- large numbers of stars
- high energy compounds
- extremely reflective ice particles

large numbers of stars