The correct option is D algae
∙ Out of the given options, cuscuta, vulture and human are heterotrophs.
∙ Heterotrophs are the organisms who depend on other living organisms for food.
∙ Cuscuta being a plant eats insects to fulfil the nutrient requirements.
∙ Vulture eats animals and humans consume both animals and plants and hence are heterotrophs.
∙ Algae, on the other hand, prepare their own food by the process of photosynthesis.