Answer:
its tongue and camouflage
Explanation:
Natural selection is the process in which the more favorable traits due to mutation that are in a select few in a population produce more offspring then others. An example of this is bacteria resistant to antibiotics due to the faster reproduction of the resistant bacteria over the non resistant ones
The correct answer is (a.) a mutation of the hemoglobin allowing better oxygen-carrying capacity. The mutation of the hemoglobin that allows a better oxygen-carrying capacity would be the most beneficial to an elephant and its descendants.