Directions: Choose a suitable one-word substitute for the given phrase from the options under each question. An animal or plant that lives in or on another animal or plant.
The correct answer is parasite. A parasite is an organism that lives on or in a host organism and gets its nourishment from or at the expense of its host. The definition perfectly matches the given phrase: "An animal or plant that lives in or on another animal or plant." The other options do not relate to this biological concept: Sycophant means a self-seeking flatterer, Bigot means a prejudiced person, Proselyte means a convert, and Chauvinist means a person displaying aggressive or exaggerated patriotism.