What evidence suggests that most of the mass of the Milky Way is in the form of dark matter?

A) The orbital speeds of stars far from the galactic center are surprisingly high.
B) Theoretical models of galaxy formation suggest that a galaxy cannot form unless it has at least 10 times as much matter as we see in the Milky Way disk.
C) Although dark matter emits no visible light, we have detected its radio emissions.
D) Our view of distant galaxies is often obscured by dark blotches, which are presumably made of dark matter.


A

Physics & Space Science

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