Option c carbon hydrogen and oxygen
A. Geographical Isolation
Explanation - Geographical Isolation alludes to the physical obstructions that exist that shield two species from mating. For instance, a types of monkey that is situated on an island can't breed with another types of monkey on the terrain.
The water separates the two species by keeping them secluded from each other and make it unthinkable for them to breed. In this case, fishes of different ponds cannot breed because they are separated from one pond to another.
