Concept:A tapeworm has no digestive system of its own, so its thin body surface is adapted for nutrient uptake.Explanation:Tapeworms live inside the host's intestine, where digested food is already present.The thin membrane covering the tapeworm's body increases the ease of diffusion and absorption.Through this thin membrane, dissolved nutrients pass directly from the host's intestine into the tapeworm's body.This adaptation is essential because the tapeworm does not have a gut or digestive tract to process food.Answer:C. Absorb digested food from the host's intestine to their system.