Answer:
Ectoparasitism. (Ans D)
Step-by-step explanation:
Parasitism is a type of relationship which is found between two species where 1 species, the parasite, gains benefits that come from the expense of the host species. Ectoparasitism is one of the examples of parasitism.
Ecto-parasitism: It is defined as a relationship where the parasite lives in the skin of the host, not within the body of the host. In this parasitism, the relationship between a host and parasite is non-mutual. In this parasitism, Ants are benefiting and aphids are being harmed.