(3 pt) Why does the author of "Healing a Wounded Heart: Daniel Hale Williams" note that, when Dr. Williams set up his medical practice, there were only three other black doctors in Chicago? A. He wants readers to think about whether they'd like to become doctors one day, too. B. He wants readers to realize that there were very few people like Williams. C. He wants readers to know the names of each of these doctors. D. He wants readers to understand that Williams had deep ties to the city of Chicago.