Question

the ozone layer is important because it protects life from damaging ultraviolet radiation. how did early life help create the ozone layer?
a water molecules on the earth were broken to release ozone.
b volcanoes released the carbon dioxide needed to make ozone.
c early bacteria and plants released the oxygen needed to make ozone.
d early bacteria and plants released the carbon dioxide needed to make ozone.

Explanation:

Ozone ($O_3$) forms when oxygen molecules ($O_2$) are split by UV radiation and recombine with single oxygen atoms. Early photosynthetic bacteria and plants produced atmospheric $O_2$ via photosynthesis, which provided the raw material for ozone formation. Options A, B, and D are incorrect because water breakdown does not directly release ozone, volcanoes do not supply the key component for ozone, and carbon dioxide is not used to make ozone.

Answer:

C. Early bacteria and plants released the oxygen needed to make ozone.