Question

question 16
what do we mean by a protogalactic cloud?
its a cloud of matter that contracts to become a galaxy
it was a term used historically to refer to any galaxy
its the cloud - like halo that surrounds the disks of spiral galaxies

Explanation:

A protogalactic cloud is a large - scale cloud of gas and dark matter that undergoes gravitational contraction to form a galaxy. It is the precursor to a galaxy. The other options are incorrect as it is not a historical term for any galaxy and not the halo around spiral galaxy disks.

Answer:

it's a cloud of matter that contracts to become a galaxy