第20题: [单项选择]Passage Three Questions 33 to 35 are based on the passage you have just heard.A. Germ-carrying insects. B. Certain strains of bacteria. C. Foul odors released from swamps. D. Creatures living near swamps. 参考答案:C 答案解析:[解析] 33-35 The term "virus" is derived from the Latin word for poison. (33)It was original