Question

which is one of edwin hubbles findings that supports the big bang theory?
the universe started at a central point.
planetesimals formed in debris disks.
visible matter only makes up about 5% of the universe.
the milky way is the only galaxy in the universe.

Explanation:

Edwin Hubble discovered that galaxies are moving away from each other, which implies that the universe is expanding. This expansion suggests that the universe had a beginning (a central point from which it started expanding), supporting the Big Bang theory. Planetesimals forming in debris disks is related to planet - formation, not the Big Bang. The idea that visible matter makes up about 5% of the universe is a more modern understanding from multiple sources, not Hubble's work. And Hubble also showed that there are other galaxies besides the Milky Way.

Answer:

The universe started at a central point.