The correct answer to this question is A, 3. This section is the secondary consumers. These consumers are organisms that consume the primary consumers. They do this for energy and it is necessary for them to survive. Along with this, they are also vital to the food chain, for they control the population of primary consumers.
Secondary consumers can be carnivores, which only eat other animals, or ominvores which eat both plants and animals. There are many different variants of secondary consumers. In aquatic environments, piranhas and sharks are examples of secondary consumers. Moles, birds, dogs, and cats are secondary consumers that exist in temperate regions.