What Supreme Court case was
reversed by the Brown decision?
A McCulloch v. Maryland
B Marbury v. Madison
C Plessy V. Ferguson
D Gibbons v. Ogden

C Plessy V. Ferguson.

Explanation:

While Plessy v. Ferguson stated that separated but equal facilities for different racial groups are not unconstitutional (thus making actual segregation of public spaces constitutional), Brown v. Board of Education said that segregated schools for children violated the US Constitution, thus reverting Plessy v. Ferguson.

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

d) a constitutional amendment