The right answer is C.
Plants know how to defend against herbivores and insects that try to eat them.
Many plant-based pesticides are made from cyanogenic glycosides (that release cyanide), which by blocking cytochrome c oxidase.
Cyanogenic glycosides are stored as inactive forms in the vacuoles of some plants. They become toxic when herbivores, by grazing the plant, break the cell membranes, which puts the glycosides in contact with the enzymes in the cytoplasm releasing hydrogen cyanide which blocks cellular respiration.
