A、By doing business. B、By buying and selling land. C、By cheating. D、By making whiskey. AHow did Johnson become rich according to

Not many years ago, a wealthy and rather strange old man named Johnson lived alone in a village in the south of England. He had made a lot of money in trading with foreign countries. When he was seventy-five, he gave some money to the village school to buy land and equipment for a children’s playground.
    As a result of his kindness, many people came to visit him. Among them was a newspaper man. During their talk, Johnson remarked that he was seventy-five and expected to live to be a hundred. The newspaperman asked him how lie managed to be healthy at seventy-five. Johnson had a sense of humor. He liked whisky and drank some each day. "I have an injection in my neck each evening," he told the newspaperman, thinking of his evening glass of whiskey.
    The newspaperman did not understand what Johnson meant. In his newspaper he reported that Johnson was seventy-five and had a daily injection in his neck. Within a week Johnson received thousands of letters from all over Britain, asking him for the secret of his daily injection.