Question

8/12 as the outer layer of the stars grow larger (from collapsing), what happens? nothing happens. they get hotter. they cool off and become reddish in color.

Explanation:

When the outer - layer of a star expands (from collapsing), its surface area increases. With the same amount of energy spread over a larger area, the temperature decreases. Cooler stars tend to be reddish in color.

Answer:

They cool off and become reddish in color.