Answer:
B: Freshwater biomes are a vital source of drinking water.
Explanation:
It's not A because oceans are part of marine biomes, and oceans contain 97% of the Earth's water and covers 71% of the Earth's surface.
It's not C because marine biomes supplies more oxygen than freshwater biomes. Marine algae supply much of the world's oxygen supply, and they take in a huge amount of atmospheric carbon dioxide.
It's not D because freshwater biomes include streams, rivers, ponds, and lakes. Aquatic biomes include oceans, coral reefs, and estuaries.
It's B because freshwater biomes are very important to our survival because they supply people with more than half of their drinking water.