Cyanobacteria,or blue-green algae,are considered the most ancient organisms capable of photosynthesis.Given what you know about cyanobacteria,which of the following is the more similar species?
A)Rickettsia rickettsii;A unicellular intracellular pathogen that infects warm-blooded animals,including humans,causing Rocky Mountain spotted fever.
B)Halobacterium salinarum;A unicellular obligate aerobe that often inhabits hypersaline lakes.This species produces gas vesicles in order to maximize its access to oxygen at the lake's surface.
C)Nitrosolobus multiformis;A unicellular rod-shaped nitrifying bacterium that inhabits subsurface soils at depths associated with plant roots.
D)Nostoc verrucosum;A filamentous species often found in shallow streams and creeks that is capable of fixing atmospheric nitrogen using specialized cells known as heterocytes.