The answer is A. It can be scientifically found while the other answer choices are all peoples personal opinions, not scientific facts like measurement.
Answer:
Animals on Earth
Explanation:
The Cambrian explosion is referred to an event which took place in the past around 530 million years ago on the Earth.
Since the event took place in the Cambrian period of the geological time scale and lead to the evolution of the diverse forms of life or organism on Earth which looked like an explosion of the species on Earth, therefore, called the Cambrian explosion.
The Explosion took place due to the evolution of a new gas called the oxygen during this period by the green bacteria which led to the formation of the diversity of animals on Earth which could absorb the Oxygen.
Thus, the first animal on Earth is correct.
When guard cells lose potassium ions, water diffuses out of the cells by osmosis. As water leaves the cells, they become flaccid and less bowed, which closes the stomata between them.