Which characteristic defines the Paleozoic era?(1 point) Responses Simple, one-celled life forms were dominant. Simple, one-celled life forms were dominant. Mammals and other warm-blooded animals became dominant. Mammals and other warm-blooded animals

Answer 1

The defining characteristic of the Paleozoic era is that it was a time when simple, one-celled life forms began to evolve into more complex organisms, including the first vertebrates and land plants. Therefore, the correct response is:

Simple, one-celled life forms were dominant.