根据听到的内容，回答 12～15 题 第 12 题 What is the main topic of the passage [A] To intr根

据听到的内容，回答 12～15 题 第 12 题 What is the main topic of the passage [A] To introduce a new type of card game. [B] To tell people how to win money in poker. [C] To compare card game with doing business. [D] To explain the origin of some expressions.