Answer: The correct option is B. Vertebrates appeared in the oceans before they moved on to land.
Vertebrate paleontology involves study of fossils of the vertebrates starting from the earliest fishes to the ancestors of modern day mammals. The spreading up of life from water to land needed modifications and adaptations such as protection from drying and support against the gravity. The tetrapod vertebrates evolved and started to live on land from oceans during the Devonian period. The succession of the Devonian period showed fossil evidences towards terrestrialization
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Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities.
The answer is Forests and Oceans. Both of them occupy most of Earth's surface, Reflects the least amount of sun, and absorbs a lot of the sun's energy due to photosynthesis and photosynthetic organisms.