单项选择题
Pushbike PerilLow speed bicycle crashes can badly injure —or even kill —children if they fall onto the ends of the handlebars.So a team of engineers is redesigning the humble handlebar in a bid to make it safer.Kristy Arbogast,a bioengineer at the Children’s Hospital of Philadelphia in Pennsylvania,began the project with her colleagues after a study of serious abdominal injuries in children in the past 30years showed that more than a third were caused by bicycle accidents.’The task was to identify how the injuries occurred and come up with some countermeasures,’she says.By interviewing the children and their parents,Arbogast and her team were able tog reconstruct many of the accidents and identified a common mechanism responsible for serious injuries.They discovered that most occur when children hit an obstacle at a slow speed,causing them to topple over5.To maintain their balance they turn the handlebars through 90degrees —but their momentum forces them into the end of the handlebars.The bike then falls over and the other end of the handlebars hits the ground,ramming it into their abdomen6.The solution the group came up with is a handgrip fitted with a spring and damping system.The spring absorbs up to 50per cent of the forces transmitted through the handlebars in an impact.The group hopes to commercialize the device,which should add only a few dollars to the cost of a bike.’But our task has been one of education because up until now,bicycle manufacturers were unaware of the problem,’says Arbogast.The team has also approached the US Consumer Product Safety Commission to try to persuade manufacturers to adopt the new design.A decision is expected later this year.
According to the passage, some engineers are trying to improve the handlebars because()
A.they are not noble enough.B.they may kill children.C.they are likely to crash.D.they make the bike move at a low speed.
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