The correct option is A. ALS is an acronym for Amyotrophic Lateral Scelerosis; it is a disease that attack nerve cells in the brain and in the spinal cord which are necessary for voluntary movement. It is a progressive neurodegenerative disease which most people lost due to respiratory failure.
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.
Hello the answer is the bacterium Streptococcus mutants that causes dental plaque formation.
Hope this helps you<3
The answer is food chain.
