Answer:
A, the sun.
Explanation:
The sun powers the water cycle and many others.
D. metabolism
i needed more letters ignore this part
Answer:
Reinforcement is the process by which natural selection increases reproductive isolation. Reinforcement can occur as follows: When two populations which have been kept apart, come back into contact, the reproductive isolation between them might be complete or incomplete. If it is complete, speciation has occurred.
Explanation:
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