Context: Below is a food web from Shenandoah National Park, a forest ecosystem in Virginia.
A food web models how the matter eaten by organisms moves through an ecosystem. The arrows in a food web represent how matter moves between organisms in an ecosystem.
Which of the following organisms is the primary consumer in this food web?
A. bolete fungus
B. silver maple
C. swallowtail caterpillar
D. black racer
From the given choices, select the correct answer and reply with the letter of the chosen option.

C