Why are galaxies in the blue cloud blue?

A) They contain hot, young stars that signify active star formation.
B) They are moving slower than stars in the red cloud.
C) They contain lots of dust that cause the bluish color.
D) They contain cold, dying stars that are fading to black.


A

Physics & Space Science

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a.
A.

b.
B.

c.
C.

d.
D.

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