It's a region located in the lowest part of water. In this case the answer would be (C) Along the bottom.
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B. synapomorphy
A synapomorphy is a shared apomorphy that distinguishes a clade from other organisms.
A clade also known as monophyletic group, is a group of organisms that consists of a common ancestor and all its lineal descendants, and represents a single "branch" on the "tree of life".
Answer:
Cyanobacteria are capable of photosynthesizing. The key difference between bacteria and cyanobacteria is that bacteria do not produce free oxygen during their photosynthesis while cyanobacteria are capable of producing free oxygen during the photosynthesis.