Fidel Castro argued that racial inequality in the United States worked against:

A. its economic success.

B. its claim to be the leader of the free world.

C. its claim to ownership of overseas colonies.

D. its political process.

It would be letter B its claim to be the leader of the free world. This is one of the biggest fallback and irony that the United States suffered during the Cold war that it is fighting in the external world but in internal state the virtues it upholds for humanity was not even follow domestically and racial inequality was still at large even the United States is a democratic country and fighting against the Communist sphere in the world.