In ancient times, there were four long-time workers speculating on the wealth of the rich man. A said that his money would not exceed 250,000 yuan. B said that his money would not exceed 300,000 yuan. C said that his money was definitely 400,000 yuan. Above, Ding said that his money certainly does not have 500,000 yuan. In fact, only one long-term worker is right. Which of the following is true to support this view? ['A is right.', "The rich's money is more than 500,000 yuan.", 'The wealth of the rich man is between 400,000 and 500,000.', 'Ding is right.']