'A person who believes that pleasure is the chief good' is Option B, Hedonist. Option A, Stoic is a person who can endure pain without complaining. Option C, Epicure means is a person who enjoys high quality food and drink. Option D, Sensual is a person who shows great interest in physical pleasures. Thus, options A, C and D are incorrect and the correct word for the given phrase is option B, Hedonist.