小安阅读Passage 42有一题疑问

In the fall of 1954, for example, C. Vann Woodward delivered a lecture series at the University of Virginia which challenged the prevailing dogma concerning the history, continuity, and uniformity of racial segregation in the South. 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.
2.        It can be inferred from the passage that the “prevailing dogma” (line 10) held that(A) Jim Crow laws were passed to give legal status to well-established discriminatory practices in the South(B) Jim Crow laws were passed to establish order and uniformity in the discriminatory practices of different southern states(C) Jim Crow laws were passed to erase the social gains that Black people had achieved since Reconstruction(D) the continuity of racial segregation in the South was disrupted by passage of Jim Crow laws（D）(E) the Jim Crow laws of the late nineteenth and early twentieth centuries were passed to reverse the effect of earlier Jim Crow laws
答案选D，我想请问C为什么不对？