单项选择题

Bill Gates, the founder of Microsoft, said that he was about to donate almost all of his tremendous fortune out of assisting the cause of global health. According to Forbes, with an estimated worth of more than $ 40 billion, the project will be a great devotion for Gates. Providing the Bill & Melinda Gates Foundation with $ 24 billion to solve global health issues, Gates made a promise that apart from "a few percent left for the kids", all his fortune will be used on the cause of global health.
So why is the richest man in the world willing to focus most of his fortune on one interest Gates believes that the theory—" the equality of opportunity" in American society—should be extended to other countries in the world. He said, to improve the health of the people has proven to be a vital method in helping poor countries to be successful in finance. "National borders may cause inequalities," said Gates, "What we all need to do is not just saying my nation has done well but taking a more global view. We have to pay more attention to these health issues, trying to know how scarce resources they have. "
"Both my parents set a good example for me when I was a child," Gates said, "My father, William H. Gates, was the head of the local Planned Birth Hood, and my mother, Mary, volunteered for the United Way. " When collecting his fortune, Gates knew he would eventually give back as well, however, he didn’t expect to devote all his energy to one project until he was about 60.
But, Gates, who is 47 now, began to question whether he could wait that long. "It seemed there was something really urgent," Gates said. "1 began to think, how many people could I save before that time\

Bill Gates will donate his vast fortune to()

A. improve American people’s health condition alone
B. improve the health of population all around the world
C. enable the government to build more hospitals
D. avoid leaving his children too much money