What role did the NAACP play in the early civil rights movement?

The NAACP-led Leadership Conference on Civil Rights, a coalition of civil rights organizations, spearheaded the drive to win passage of the major civil rights legislation of the era: the Civil Rights Act of 1957; the Civil Rights Act of 1964; the Voting Rights Act of 1965; and the Fair Housing Act of 1968.

the answer to your question is a. the salt plains

in 1811, he led an expedition, known as the george c. sibley expedition, to improve relations with the pawnee and kansa tribes, and also to locate the rumored jefferson's salt mountain