Many Americans accepted which of the following beliefs in the 1950s?

Many Americans accepted which of the following beliefs in the 1950s?
 
  a. The diversity within American society means that tension and conflict are inevitable in the United States.
  b. Citizens in a mass democracy must always harbor a healthy distrust of their elected officials and questiontheir decisions.
 c. Americans must work to bring about the moral regeneration of American society.
  d. As the United States struggles against the Soviet Union for the future of the world, critics of America aresuspect and perhaps even unpatriotic.