Cyanobacteria are believed to generate the majority of oxygen gas in earth’s atmosphere. what allows them to produce oxygen?
a. photosynthesis in which h2s is the electron source.
b. photosynthesis in which water photolysis produces h , e , and o2.
c. bacteriorhodopsin-based photosynthesis.
d. all of the above.
e. none of the above.

b. photosynthesis in which water photolysis produces H , e , and O2 is the correct answer.

Explanation:

Cyanobacteria is the oxygenic microbes that produce oxygen by a process called photosynthesis.Photolysis is the process  by which water molecules split into oxygen and hydrogen during the light reaction of the photosynthesis process.Cyanobacteria produce their food by photosynthesis.Cyanobacteria has chlorophyll that converts carbon dioxide to sugar by carbon fixation.Cyanobacteria perform photosynthesis by using carbon dioxide, sunlight, and water to produce oxygen and carbohydrates.Thus cyanobacteria utilize the energy from light to split the water molecule and produces H, e , and O2.