How Do Astronomers Measure the Relative Amounts of Dark Matter

Multiple Choice

How do astronomers measure the relative amounts of dark matter and luminous matter in the early universe?

A) The same way they do in the present universe: rotation curves, gravitational lensing, etc.
B) By measuring the sizes of the peaks created by acoustic waves in the cosmic microwave background.
C) By measuring the relative amplitudes in the acoustic overtone waves in the cosmic microwave background.
D) By measuring the relative frequencies in the acoustic overtone waves in the cosmic microwave background.