Aresearcher was studying mutations in bacteria. he found that certain bacteria had changes in their dna that allowed them to be resistant to antibiotics

humans can cause extinction of a species through overharvesting, pollution, habitat destruction, introduction of invasive species (such as new predators and food competitors), overhunting, and other influences. explosive, unsustainable human population growth is an essential cause of the extinction crisis.

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i didn't have the answer choices , but i tried my best.