B. tiredness

　　C. relief

　　D. disappointment

　　4. What did Wright's team discover from their experiment?

　　A. Those staying outdoors reset the clock inside their bodies over a short period.

　　B. The body clocks of the two groups didn't show much difference.

　　C. The body clocks of those who stayed at home remained the same.

　　D. Changes to the body clock don't necessarily affect melatonin levels in our bodies.

　　5. According to the passage, to change our sleeping habit, we' d better_ .

　　A. stay home to reset our body clock and get more sleep

　　B. stay up late long past sunset and sleep long after sunrise

　　C. get exposed to more natural light but less artificial light

　　D. try to reduce melatonin levels as much as possible at night

　　6. What is the author's main purpose of writing the passage?

　　A. To inform us of a possible way to adjust the body clock.

　　B. To explain how a lack of sleep is bad for our health.

　　C. To analyze how the body clock influences our sleeping habits.

　　D. To explore how the body clock is connected with melatonin levels.

　　C

　　The death of the plastic credit card could be a step closer as high street names including McDonald's and the Co-op prepare to test a breakthrough finger-scanning payment technology.

　　FingoPay, developed by British start-up Sthaler, uses a biometric reader to scan the veins of a shopper's finger, building up a "map" that is unique to each individual.

　　By connecting this pattern with a credit card or bank account, the company plans to let shoppers pay simply by placing their finger in a pocket-sized scanner, doing away with cash and credit cards.

　　Sthaler, founded by former music industry executive Nick Dryden, will begin testing the technology next month in Proud, a London nightclub. Mr. Dryden said McDonald's is experimenting with a pilot of the technology, and that Sthaler is also planning a project with Co-op's food stores.

It comes amid growing interest in using biometric identification in payments, which backers believe are more secure and efficient than passwords and PINs. Apple Pay, which uses the iPhone's fingerprint technology, launched in