Answer:
A tan might indicate sun damage to the skin.
Explanation:
Tanning is the process by which the skin is exposed to the ultraviolet rays that comes from the sun with the purpose of producing a dark-brown coloration called a TAN.
A tan achieved by exposure to the sun can actually indicate that a person's skin is undergoing damage from the UV rays of the sun, hence, the skin responds by producing a protein called melanin, which protects the skin and later forms the dark coloration- tan. From this explanation, tan is got in response to a damaging signal received by the cell, hence, a tan might indicate sun damage to the skin.
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.
A unicellular or single celled organism is the term for organisms composed of only one cell.
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