Listen to the text and decide which of the following best states the author's purpose.<br/> <br/> A、To condemn with the author's own experience of racial discrimination in American society as late as the 1940s.<br/> B、To describe the author's trip with her family to Washington D.C. as a graduation present.<br/> C、To disclose the fact that the black people were still leading a poor life in the United States.<br/> D、To tell the readers that her first trip to Washington D.C. was really a worthwhile graduation gift.