The correct answer is “Because Hurston uses American English in her novel only occasionally; she clearly feels that her people should be committed to their own language” and “By placing American English and Black English side by side in her novel, Hurston seems to emphasize their nature as separate languages”.
Indeed, Hurston was unconcerned about racial issues and she was criticized by the African American intelligentsia due to that fact. Thus, she is not hostile to white readers, especially considering the fact that the main character is acquitted of murder charges by an all-white, female jury. Also the fact that she conveys all the specific characteristics of Black English does not mean necessarily that she considers it “a language”, Mark Twain did the same with this and several other Southern dialects, both white and black and his intent was only to convey a clear picture of the local vernacular.
Baldwin posits that “because Hurston uses American English in her novel only occasionally, she clearly feels that her people should be committed to their own language”. It is certainly a possible interpretation of her literary choices, in any event she did consider that African Americans had their own distinct identity and such identity is reflected in their vernacular. Finally, it is true that it can be concluded that both Black English and American English are separate linguistic entities from the juxtaposed opposition she operates with the two in her book.
