Answer:
B. photosynthesis and respiration keep the levels of oxygen and carbon dioxide fairly constant in the atmosphere.
Explanation:
Answer:
B
Explanation:
Angiosperms are a major division of plant life, which make up the majority of all plants on Earth. ... They quickly gained an advantage over the previously dominant plant type – gymnosperms – for two reasons. Angiosperms' use of flowers to reproduce made them more reproductively successful.
I believe the answer is A, Ray crystallography
