Which theme does Carson McCullers build around the existential issues the main characters face in The Heart Is a Lonely Hunter, as revealed through these lines from the novel?
Some kind of music was too private to sing in a house cram fall of people. It was funny, too, how lonesome a person could be in a crowded house.
religion as self-delusion
the significance of moral education
man's struggle against isolation
materialism versus personal values

Question

Which theme does Carson McCullers build around the existential issues the main characters face in The Heart Is a Lonely Hunter, as revealed through these lines from the novel? 
Some kind of music was too private to sing in a house cram fall of people. It was funny, too, how lonesome a person could be in a crowded house.
religion as self-delusion
the significance of moral education
man's struggle against isolation
materialism versus personal values