Biology

The correct answer is B.starfish.

The starfish (specifically the Pisaster ochraceus species) is the keystone predator found in the tidal pools of northwestern North America. It was the species that led ecologist Robert Paine to develop the keystone species concept. Paine's studies in the 1960s showed that the starfish, by preying on mussels, helped maintain the biodiversity of the ecosystem. Without starfish, mussel populations exploded, reducing the variety of other species in the tidal pool.

Here’s a brief explanation of the other options:

A.Sea otters: Another example of a keystone predator, pa...