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Three reasons a species could become extinct include, deforestation, being overhunted, not enough food available.
Answer: Paleozoic
Explanation: The Paleozoic Era, which ran from about 542 million years ago to 251 million years ago, was a time of great change on Earth. The era began with the breakup of one supercontinent and the formation of another plants became widespread. And the first vertebrate animals colonized land.
Answer: Mechanical Isolation
Explanation:
Mechanical isolation is a type of barrier that prevents the species that are closely related from mating with each other.
It is used in case of plants and animals(here beetles) in which the without compatible sex organs individual of different species will not be able to mate and produce offspring.
Thus, the correct answer is option C
