Which civil rights leader was central to the success of the march on washington in august 1963?
rosa parks
malcolm x
thurgood marshall
martin luther king, jr.

The Civil Rights leader that was central to the success of the March on Washington in August 1963 was Martin Luther King Jr.

Explanation:

The March on Washington for Jobs and Freedom was a demonstration held on August 28, 1963 in Washington D.C. to stand up for the rights of African-American citizens. After the march Martin Luther King gave his famous speech I Have a Dream in the National Mall. The march was organized by A. Philip Randolph and Bayard Rustin and managed to mobilize between 200,000 and 300,000 people.  

The march followed earlier demonstrations, including the Birmingham campaign earlier that year and contributed to the adoption of the Civil Rights Act of 1964.

by creating a labor shortage that pushed the continent toward a market economy

the answers is b.   environments.