It Has Been Suggested That Cyanobacteria Are the Most Important

Multiple Choice

It has been suggested that cyanobacteria are the most important organisms to have evolved on the Earth. What evidence justifies this view?

A) Some cyanobacteria can fix nitrogen (which plants need in order to produce oxygen) , making them unique among bacteria.
B) Some cyanobacteria differentiate to form multiple cell types, making them the ancestors of plants and animals.
C) Cyanobacteria evolved the ability to use water as an electron donor in photosynthesis, generating the oxygen gas found in the atmosphere.
D) Cyanobacteria form microbial mats, enabling them to spread across lake bottoms and shallow seafloors.