Bio help: Which is all secondary consumers?

C. It is not A because mosquito larvae are primary consumers (well, except for a couple of species). It is not B because many zooplankton are also primary consumers. It is not D, because water plants are primary producers. That leaves only C. Mountain Whitefish is not completely a secondary consumer, being a voracious consumer of many different kinds of life, but for the most part is indeed a secondary consumer, and northern pike and herons most certainly are.