Which statement correctly describes the four life stages of hard ticks and the typical hosts associated with each stage?

• A. Egg, larva, nymph, and adult; larvae and nymphs feed on small mammals or birds, while adults feed on larger hosts such as deer and humans.
• B. Eggs, larvae, nymphs, and adults; all stages feed only on plants.
• C. Egg, larva, nymph, and adult; larvae feed on fish, nymphs on amphibians, adults on large mammals.
• D. Egg, larvae, nymph, and adult; eggs hatch into larvae that feed on large mammals; adults feed on birds.

Answer: (A)

Hard ticks go through a four-stage life cycle—egg, larva, nymph, and adult—and each stage needs a blood meal from a host. The size of the typical host tends to increase as they progress through stages. The larva and nymph usually feed on small mammals or birds, which is how they get their first meals and continue developing. In the adult stage, they target larger hosts, with deer being a common choice for many species, and humans often serving as incidental hosts when ticks are questing in the environment. This pattern matches the statement by listing the four stages and linking larvae and nymphs to small hosts and adults to larger hosts like deer and humans. The other options misstate either the feeding behavior (ticks don’t feed on plants) or the host associations for the stages.