Concept:The part connecting the middle ear to the pharynx is the Eustachian tube.Explanation:The middle ear needs to equalise pressure with the outside air.This is done through a narrow canal called the Eustachian tube.The Eustachian tube opens into the upper part of the pharynx, known as the nasopharynx.In the given diagram, this tube is labelled III.Answer:C. III
