Final answer:
W.E.B. Du Bois, the first African American Ph.D. from Harvard, was a crucial figure in the establishment of the NAACP and advocate for the full political rights of Blacks in America.
Step-by-step explanation:
The individual who believed that the granting of full political rights to Blacks was essential to their social and economic progress, and who helped to found the NAACP, was W.E.B. Du Bois. Du Bois was a pivotal figure in the history of civil rights and the battle against racial inequality in the United States. He was the first African American to earn a Ph.D. from Harvard and later worked as the director of publications for the NAACP, where he also edited its journal, The Crisis. Du Bois was a proponent of the Niagara Movement, which led to the founding of the NAACP and called for immediate political, economic, and social equality for African Americans.