Genetic variation is the variation in the DNA sequence in the genome of an organisms. Organisms of a species have similar characteristics but they are not identical due to genetic variation. Genetic variation is important in the survival and the adaptability of a given species of organism. Therefore, in this case lack of genetic variation necessary to adapt to change in the environment will lead to extinction of the fish species that lacks the variation.
Answer:
I believe the answer would be A
The Krebs cycle occurs in the mitochondrial matrix of a cell.
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