Environmental factors do influence natural selection because they can increase or decrease the population of a species, by selecting those with only favorable traits.
The green pigment chlorophyll
<span>If a nurse notices that an accident victim cannot clench his teeth, there is a good chance that his trigeminal nerve has been affected. This nerve is located inside the brain and its primary purpose is to transmit sensations from a person's face to the brain. Damage to this nerve could cause the patient to be unable to clench their teeth.</span>
C. Dinosaur footprint as it is the only body part that is stated in the choices.
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