再问大全Passage 42

gamxiaoyuan

原文对应句：He argued that the Jim Crow laws of the late nineteenth and early twentieth centuries not only codified traditional practice but also were a determined effort to erase the considerable progress made by Black people during and after Reconstruction in the 1870’s
问题： Which of the following best describes the new idea expressed by C. Vann Woodward in his University of Virginia lectures in 1954?
(A) Southern racial segregation was continuous and uniform.
(B) Black people made considerable progress only after Reconstruction.
(C) Jim Crow legislation was conventional in nature.
(D) Jim Crow laws did not go as far in codifying traditional practice as they might have.
(E) Jim Crow laws did much more than merely reinforce a tradition of segregation.
这题选E，我想问下C为什么不对呢？ conventional in nature不就等于 codified traditional practice么？