Biology

The correct answer is apex predators.

Many keystone species are apex predators, meaning they are at the top of the food chain and have a significant impact on the structure and balance of the ecosystem. Apex predators help regulate populations of prey species and maintain the health of the ecosystem by controlling the abundance and diversity of other organisms.

Why the other options are incorrect:

1.Secondary predators: These are predators that feed on other predators or herbivores but are not typically at the top of the food chain. While they may be important, they aren't typically considered keystone species in the same way ape...