The correct answer is true.
It is true that most Puerto Ricans would prefer to be their own independent nation, separate from the US.
Puerto Rico became part of the United States as a "protectorate," after the Spanish-American War. However, the culture, traditions, and history of Puerto Rico are completely different from the American culture. Puerto Rico is not a state of the Union, it is a protectorate. It has never been considered to be a state. Puerto Rico is a poor country. Puerto Ricans still speaking Spanish, and have more similarities to other Caribbean people and South American people, than affinities with the United States.