Caves from geographically separated parts of the world show a similar pattern of supporting organisms without eyes or pigment. This is true even among groups that are not closely related (e. g., fishes and arthropods). What additional conclusion might you draw from these observations of cave animals that is consistent with your knowledge of evolution through natural selection

rain is the best answer

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation:

the sun's light combined with the visible wavelenghts form what is called ultraviolet radiation, which are the long waves at the end of a visible light sprectrum.

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