Why Did Congress Feel It Was Important to Pass the Fourteenth

Why did Congress feel it was important to pass the Fourteenth Amendment although the recently passed Civil Rights Act had the same purpose?

A) President Johnson had vetoed the Civil Rights Act in an effort to thwart racial equality.
B) The Civil Rights Act did not clearly define the rights of all citizens regardless of race.
C) The Civil Rights Act could be overturned by a future Congress, but an amendment made it a permanent part of the Constitution.
D) The Civil Rights Act did not go far enough in eliminating the Black Codes that deprived citizens of "fundamental rights."