According to the passage which one of the following is true of Black folklore traditions as used in literature written in the United States? A. They are an aspect of Black American literature first recognized and written about by Henry Louis Gates, Jr. B. They were not widely incorporated into novels written by Black Americans until after the 1940s. C. They were first used by a novelist in Zora Neale Hurston's Their Eyes Were Watching God. D. They were not incorporated into novels published by Black Americans in the 1940s. E. They are an aspect of Black literature that some readers did not fully appreciate until relatively recently.