答案：D

考查prefer和would rather的用法区别。“宁愿......而不愿......”prefer to do sth.；prefer doing to doing；“宁愿某人做某事”prefer sb. to do sth.；would rather do sth. than do sth.。would rather后常跟动词，prefer后可以跟名词。句意“他经常说：‘我宁愿心存一百万个微笑，也不愿口袋中有十亿元。’”故选D。