Answer: The nervous system has two main parts:
The central nervous system is made up of the brain and spinal cord.
The peripheral nervous system is made up of nerves that branch off from the spinal cord and extend to all parts of the body.
Explanation:
The best and most correct answer among the choices provided by your question is the fourth choice or letter D. Reptiles are the most critically endangered animal group. Their population is threatened due to illegal activities done by man like poaching.
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Two identical DNA strands