Which Statement Best Describes the Thesis of David Riesman's Book

Which statement best describes the thesis of David Riesman's book The Lonely Crowd?

A) White America had alienated black Americans from mainstream society.
B) Americans were conformists and lacked the inner resources to lead truly independent lives.
C) Women were unhappy with the role of wife and mother and longed for acceptance in higher education and other intellectual pursuits.
D) After World War II, Europe was left behind economically and politically with the emergence of the United States and Soviet Union as superpowers.