What is a lampricide specifically used for?

A lampricide is a chemical specifically designed to target and kill lamprey larvae. Lampreys are parasitic fish that can cause significant ecological and economic damage, particularly in freshwater ecosystems. The use of lampricides is part of management practices aimed at controlling invasive species and protecting native fish populations.

In this context, while other options mention methods for pest control or ecological management, none of them pertain to the specific action and purpose of lampricides. For instance, killing adult fish or controlling mosquito populations involves different classes of pesticides or methods entirely, while algae control would require herbicides rather than lampricides. Thus, the choice of option C accurately reflects the unique role of lampricides in managing lamprey populations specifically, which is crucial for maintaining healthy aquatic ecosystems.