Through the example of pilots, the author is tryin

单项选择题

Inhaling pure oxygen for 30 seconds can double your recall of what happens in the next couple of minutes, according to researchers who addressed the annual meeting of the British Psychological Society in London this week. They say the effect lasts for 24 hours. The stimulating influence of oxygen is well-established folk wisdom among professions with access to the gas. Pilots sometimes pass the time by trying to memorise lists of passengers" names and where they are seated, and an oxygen boost makes the task easier, says Andrew Scholey, a psychologist at the University of Northumbria in Newcastle upon Tyne. Now Scholey and his colleague Mark Moss say they have conclusively shown in six controlled trials that oxygen significantly improves short-term memory, reaction time and attentiveness. A mask supplied some participants with pure oxygen and the others with ordinary air, which is about 20 percent oxygen. Neither group knew which type of gas they were inhaling. The volunteers then listened to a series of 15 words. Six minutes later they were asked to remember as many of the words as possible. The participants who inhaled air remembered only 4 or 5 words - but those who imbibed oxygen recalled 8 or 9. Too little or too much oxygen will not have the desired effect, the researchers discovered. The optimal exposure time ranges from 30 seconds to a minute, they say. And since the oxygen only lasts a couple of minutes in the body before it reacts with other molecules, volunteers have to be exposed to information soon after inhaling, though the improved recall can last up to 24 hours, says Scholey. So, should cramming students be sniffing oxygen instead of bingeing on caffeine Probably not, since high levels of oxygen damage living tissue. Scholey thinks that oxygen-enriched study chambers will remain science fiction. "The only advice I have is not to revise at the top of a mountain." And as the festive season gets into full swing, the experience of deep-sea divers may be especially useful. "Divers have told me they have a blast of oxygen to get rid of hangovers," Scholey says. But he warns enthusiasts not to try it at home.

Through the example of pilots, the author is trying to tell us that______.

A．oxygen helps memorize passengers" names better in the air than on the ground
B．oxygen helps develop a habit of memorizing passengers" names
C．oxygen can make it easy to kill time in the air
D．oxygen has a stimulating influence on memory