Most people who travel long distance complain of jetlag. Jetlag makes business travelers less productive and more prone【C1】______ making mistakes. It is actually caused by disruption of your "body clock"—a small cluster of brain cells that controls the timing of biological【C2】______ . The body clock is designed for a regular rhythm of daylight and darkness, so that it is thrown out of balance when it【C3】______ daylight and darkness at the "wrong" times in a new time zone. The【C4】______ of jetlag of ten persist for days while the internal body clock slowly adjusts to the new time zone. Now a new anti-jetlag system is【C5】______ that is based on proven【C6】______ pioneering scientific research. Dr. Martin Mooreede had devised a practical strategy to adjust the body clock much sooner to the new time zone【C7】______ controlled exposure to bright light. The time zone shift is easy to accomplish and eliminates【C8】______ of the discomfort of jetlag. A successful time zone shift depends on knowing the exact times to either【C9】______ or avoid bright light. Exposure to light at the wrong time can actually make jetlag worse. The proper schedule for light exposure depends a great deal on【C10】______ travel plans.
单选题
【C1】
【正确答案】
D
【答案解析】解析：词组be prone to(do)sth．为固定搭配，其含义是“有……的倾向，易于……”。如：This part of the road is prone to accidents．(这段道路容易出事故。)
【答案解析】解析：本句可译为：“因跨越时区而导致的不适症状通常会持续数天。”D项symptoms“症状”最符合原文。首先，这种不适并不属于疾病的范畴，因此C项可以排除。A项signs意为“标志，迹象，征兆”。例如：There are no signs of life about the house．(这所房子没有住人的迹象。)B项defects通常指事物“固有的、先天的缺陷”。