单选题
. Questions refer to the following article.
21. How did Ron Jefferson earn his money?______
21. How did Ron Jefferson earn his money?______
【正确答案】
D
【答案解析】 选项A错误，文中提到野山羊协会是受捐方。选项B错误，Jefferson在写这本书时已经是富翁。选项C错误，这是他捐款的目的之一。选项D正确。