D.
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Adapt their breathing rate due to less air pressure being pushed on them.
According to one major language theory, how did different groups develop their own languages?
Answer: There are two main theories that explain how different groups developed their own languages. The major one is that humans at some point in time evolved a language acquisition device.
I hope it helps, Regards.
Answer and Explanation: The civil war wasn't avoidable because of the disagreement and hate between the North and the South.
