In the Early Universe,why Were Inhomogeneities in the Distribution of Normal

Multiple Choice

In the early universe,why were inhomogeneities in the distribution of normal matter much smaller than the inhomogeneities in the dark matter?

A) Radiation pressure affected normal matter but not dark matter.
B) Magnetic fields smoothed the distribution of charged particles in the normal matter but not in dark matter.
C) Dark matter particles were more massive and cooled off before normal matter,thus dark matter fluctuations had a longer time over which to grow.
D) Dark matter was ten times more massive than normal matter.