Question

jet lag is a problem suffered by many flight attendants, pilots, and frequent flyers. when people travel rapidly across numerous time zones, as they do when flying long distances, they sometimes develop a condition called jet lag. these long trips disturb normal body rhythms. after a trip, travelers may have trouble falling asleep at night and staying awake during the day. experts advise travelers flying eastbound to go to bed later than usual before traveling and those flying west to go to bed earlier than usual. these changes should help minimize the effects of jet lag. which statement best summarizes this paragraph?
a. flight attendants, pilots, and frequent flyers often suffer jet lag. experts have many tips for travelers that will help prevent jet lag.
b. jet lag is a problem for people who fly a lot. to prevent jet lag, people can change the time they go to sleep before they take a trip.
c. people who suffer jet lag have trouble falling asleep and staying awake. this is because peoples body rhythms get thrown off by travel.
d. long - distance travel is unsafe because of a condition known as jet lag. jet lag happens when people travel across many time zones.

Explanation:

The passage discusses jet lag, its effects on flight - related personnel (flight attendants, pilots, frequent flyers), and how travelers can prevent it by changing sleep times (e.g., going to bed earlier or later). Option A only mentions flight attendants, pilots, and frequent flyers suffering jet lag but doesn't cover prevention. Option B focuses on jet lag as a problem for frequent flyers and prevention by changing sleep times, but it's too narrow. Option C only talks about people with jet lag having sleep problems. Option D comprehensively covers that long - distance travel (across many time zones) causes jet lag (a condition) which disturbs body rhythms and mentions experts' advice (changes in sleep times) to minimize its effects.

Answer:

D. Long - distance travel is unsafe because of a condition known as jet lag. Jet lag happens when people travel across many time zones. Experts advise travelers flying eastbound to go to bed later than usual. These changes should help minimize the effects of jet lag.