A、He described it in a realistic way. B、He was very imaginative. C、His tone was calm. D、He never told jokes. A

Americans like to laugh and make jokes, especially practical jokes.  These jokes, intended to trick or deceive people in some harmless way, and are always popular. In the United States and a few other countries the first day of April, April Fool’s Day, is a day devoted to such harmless practical jokes and an excuse for every American to fool his friends and neighbors.
    When I was a college student, our daily college newspaper, which was read by most of the people who lived in the city near the college as well as by students, always had a special April Fool’s Edition.  One year the paper said that a beautiful park in the center of the campus was to be turned into a parking lot.
    Another year the paper falsely reported that a Russian submarine had been seen in the lake which is on the campus.  It was surprising that many people believed these stories.  But probably the most successful practical being invaded by people from Mars.  His description of this invasion from outer space was so realistic that he caused a panic and was actualy responsible for the deaths of several people.