Write a multi-choice question for the following article, with the given choices and answer: Article: Yu Pengnian is an 88-year-old real estate Chinese businessman. He amassed a fortune of $1.3 billion dollars during his career but instead of keeping the money and living like an emperor, he decided to give it all away. All of his fortune will be spent on helping poor Chinese students get a better education. And Yu isn't the only super-rich person in China who has this spirit of giving. Chen Guangbiao, a Jiangsu recycling tycoon, has given millions of dollars to charity and promises to give all of his money to charity when he dies. Yu and Chen are among the many businessmen who have become prosperous during China's economic rise. An American business magazine, Forbes, estimates that there are 117 billionaires in China and hundreds of thousands of millionaires. What sets Yu and Chen apart from the rest, though, is their tremendous generosity(,) when it comes to donating money to charity. Last week Bill Gates and Warren Buffett came to Beijing. Gates and Buffett, two of the world's richest men, are also the world's biggest philanthropists. They invited fifty of China's richest people to have dinner with them and talk about the spirit of giving. At first, only a few people accepted their invitation. It seemed some of the invited guests were afraid that Buffett and Gates were going to pressure them into giving their wealth to charity. A lot of people are angry at the billionaires who are not willing to give away their fortunes. They _ hem for being miserly and not caring about the poor and the less fortunate. But I think this criticism is wrong. A gift, any gift, should come from the heart. Instead of criticism, these reluctant billionaires should be encouraged to follow the examples of Yu Pengnian and Chen Guangbiao. Encouragement is always a better strategy than criticism. As we say in English, "You can catch more flies with honey than with vinegar." Options: A The author wants to tell us that flies prefer honey to vinegar. B The author wants to prove that encouragement is always a better strategy than criticism when it comes to charity. C The English saying expresses the main theme of the passage. D The author wants to criticize those billionaires who are not willing to give away their fortunes and not caring about the poor and the less fortunate. Answer: B The author wants to prove that encouragement is always a better strategy than criticism when it comes to charity. Question:
The answer to this question is:
According to passage, why does the author end the passage with the English saying "You can catch more flies with honey than with vinegar"?