All matter Mass and time that exists and has ever existed is contained in which of the following the sun
the planets
the milky way
the universe

The Milky Way

Explanation:

The Milky Way not only contains mass and time but it contains all of the solar systems, dust, maybe a black hole, and a lot of stars which is matter. Milky Way is a galaxy in a universe that contains a lot of planets it also contains mass and time.

It hasn't been confirmed nor denied but it is known that the milky way contains dark matter which is another type of matter and mass.

Hope this helped :)