The phrase " a wall of separation between church and state" is a metaphor that appears in to describe the a) a letter, ideas of the founding fathers. b) the constitution, idea of religious liberty c ) the constitution, first amendment d) a letter, first amendment

Im not sure about this, but i think it is,

B) The constitution, idea of religious liberty.

It might not be correct, but it was what i understood from -
http://www.wallofseparation.us/the-origins-of-wall-of-separation/
I hope this helps!

Best B. It reinforced segregation and discrimination.

Booker T. Washington (1856-1915) advocated gradualism.  That meant being patient and doing what white society would allow, which meant changes and better times for blacks would come slowly.

A different point of view was taken by W.E.B. Du Bois (1868-1963).  Du Bois noted that Washington's approach was not accomplishing any real gains for blacks.  He also felt that Washington's point of view showed acceptance of the racial inferiority of blacks.  Plus he saw that institutions in the black community were being dominated by persons like Washington, rather than really empowering all individuals for themselves.  Du Bois argued that all black citizens should have the right to vote, equality as citizens, and access to education according to their abilities, and his approach was more confrontational, attacking segregation using protests, lawsuits, and publications.   Du Bois was strongly active in the National Association for the Advancement of Colored People (NAACP).