In what era did the plants begin to flourish?

Precambrian

Paleozoic

Mesozoic

Cenozoic

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.