The answer is D. Tertiary Consumer.
A producer is an organism that can make its own food from inorganic substances. Plants are the most common producers.
A primary consumer is an organism that eats plants. Animals that eat plants are called herbivores.
A secondary consumer is an organism that eats primary consumers. Animals that eat herbivores are called carnivores.
A tertiary consumer is an organism that eats secondary consumers. Animals that eat carnivores are called top predators.
In the case of a hawk that eats a frog, the hawk is a tertiary consumer because it eats a secondary consumer (the frog).