Junie759
Answered


A primary reason for the passage of the 14th
amendment in 1868 was to
(1) prohibit the secession of states
(2) uphold the legality of the Black Codes
(3) continue the presidential plan for Reconstruction
(4) guarantee citizenship rights to the newly
freed slaves



Answer :

A primary reason for the passage of the 14th amendment in 1868 was to "(4) guarantee citizenship rights to the newly freed slaves" but unfortunately segregation occurred. 
The 13th, 14th, and 15th Amendments were put into effect after the Civil War to abolish slavery and grant blacks equal rights (at least in theory and on paper). 

In light of that, 1 makes no sense, as the 14th amendment was post-Civil War. 
2, the Black Codes, were codes used by the Confederacy in the Civil War. Again, makes no sense
3 is plausible, as the 14th amendment was one of the Reconstruction Amendments
4 Is the best answer though, as it is the the main part of the 14th amendment, and thus the primary reason for its radification

hope that helps!