Biology

The correct answer is C.keystone species.

Both sea otters and sea stars are considered keystone species because they have a significant impact on their ecosystems.

1.Sea otters help maintain kelp forest ecosystems by preying on sea urchins, which are herbivores that graze on kelp. Without sea otters, sea urchin populations would explode, overgrazing and potentially destroying kelp forests, which are vital marine habitats.

2.Sea stars, specifically the Pisaster ochraceus (Ochre sea star), are keystone predators in tide pool ecosystems. They prey on mussels, which would otherwise dominate and outcomp...