Why Are the Youngest Galaxies That Are Seen in Distant

Multiple Choice

Why are the youngest galaxies that are seen in distant parts of the universe bluer and brighter than the older, closer galaxies observed?

A) The red light has been partially absorbed by gas and dust between Earth and the galaxies.
B) Young galaxies have more dust, and dust scatters blue light better than red.
C) The light from the most distant galaxies has been bent by gravitational lenses and focused on Earth.
D) Young galaxies have a burst of star formation that produces many hot, bright, blue stars.