Therapist: The ability to trust other people is essential to happiness, for without trust there can be no meaningful emotional connection to another human being, and without meaningful emotional connections to others we feel isolated. Which one of the following, if assumed, allows the conclusion of the therapist's argument to be properly inferred? ['Anyone who is able to trust other people has a meaningful emotional connection to at least one other human being.', 'To avoid feeling isolated, it is essential to trust other people.', 'No one who is feeling isolated can feel happy.', 'Anyone who has a meaningful emotional connection to another human being can be happy.']