Answer:
The correct answer is "C. Cave fish have evolved degenerated eyes because they have no use for vision in dark, underwater caves."
Explanation:
All of these statements about organism adaptation to its environment are true, but the real reason why cave-fish are blind is not because there's no use for their eyes in the dark, but because being blind saves them energy, as using one's vision requires the activity of photoreceptive cells and neurons, and underground caves are lacking in both food and oxygen.
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Explanation:
heat (metal or glass) and allow it to cool slowly, in order to remove internal stresses and toughen it.
OR
recombine (DNA) in the double-stranded form following separation by heat.
