The success of the civil rights movement in the years 1947 to 1957 was dependent on the NAACP [National Association for the Advancement of Colored People]? (past exam question)

There are different approaches to this question but it is important in the introduction to establish how important the NAACP was a factor but also the other factors at play, which here include the efforts of other civil rights groups, the role of the federal government and how opposition limited the success of the NAACP. The introduction should have a clear argument; mine would be the NAACP were the strongest and most successful factor at this time but it cannot be considered in isolation.My argument is (briefly) as follows:
The progress the NAACP made through legal court cases was vital to the civil rights movement in this period  
Examples: 1947 Morgan vs Virginia case ruling that discrimination on interstate buses was illegal; 1950 Sweatt vs Painter ruling that the University of Texas law school for blacks was not equal to that of whites; 1954 Brown vs Board of Education ruling that segregated schools were unconstitutional.
However, other civil rights groups made progress that helped the NAACP
Examples: CORE had almost 50 national chapters by the end of the 1950s, led Journey of Reconciliation 1947 to challenge segregation on interstate buses; Montgomery Improvement Association and Martin Luther King led the Montgomery Bus Boycott 1955-6 which led to the 1956 NAACP-led case Bowder vs Gayle which desegregated these buses
The extent of white opposition brings into question how successful the NAACP were
Examples: Despite 1954 Brown vs Board, by 1968 68% African-American students still attended segregated schools; 101 Southern Senators signed the Southern Manifesto in 1956 to resist integration in schools; by 1956 White Citizen’s Councils had 250,000 members
The federal government made some progress on civil rights too, it was not just the NAACP
Examples: 1948 Truman desegregated the army by executive order; 1957 Eisenhower sent 1,000 troops to Little Rock to forcefully desegregate the school