40. Why does the author start talking about the political situation of blacks in the third paragraph? (A) To illustrate the condition of "responsive pluralism" (B) To indicate the progress in advancing racial minorities' democratic rights of citizenship (C) To advocate blacks' capacities in competing as players in the electoral arena (D) To demonstrate the importance of achieving "stratified pluralism" (E) To give an example of the denial of full citizenship for minority groups in U.S. history