From which of the following do spiral galaxies form?
AHigh-density proto-galactic clouds
BRapidly spinning proto-galactic clouds
CColliding/merging proto-galactic clouds
DRapidly cooling proto-galactic clouds
AHigh-density proto-galactic clouds
BRapidly spinning proto-galactic clouds
CColliding/merging proto-galactic clouds
DRapidly cooling proto-galactic clouds