Everyone knows that the first rule of driving is never taking your eyes off the road. Teen

drivers【C1】______being careful, but they tend to start multitasking after just a few months behind the wheel, according to research published Tuesday. And【C2】______older drivers can handle eating or talking to passengers, which【C3】______up the new drivers, dialing a cell phone increased the risk of accidents among young and【C4】______drivers alike. This isnt great news, since its well【C5】______that distracted driving is a leading cause of accidents among all drivers. It makes sense that young drivers will start testing their limits after a few months behind the wheel, according to Bruce Simons-Morton, a behavioral scientist. "You increase the difficulty of a task until you make an【C6】______," Simons-Morton says. "It seems like a very natural thing but still its very【C7】______, because good driving ability and safety judgment develops【C8】______a very long period of time." Within six months of getting their licenses, young drivers in this study -started texting, eating and【C9】______the radio while driving as much as their more skilled【C10】______But it takes thousands of hours of【C11】______to get good at driving, according to Simons-Morton. That disconnect may help【C12】______the high accident rates among teenage drivers. The researchers compared data from two small studies—one tracked 42【C13】______licensed young drivers and the other looked at 100 drivers with more experience . All the participants had sensors and cameras【C14】______in their cars. The researchers used the sensors to track when drivers got into accidents or close calls. The videos were then used to see what the drivers were doing just before the accidents【C15】______. Because the researchers wanted to focus on the【C16】______of distracted driving, they【C17】______crashes caused by drunk driving and ones that were clearly caused by other drivers. Since the number of people in this study was small, Simons-Morton says the results will have to be【C18】______by other research. A couple of bigger studies already【C19】______the works, might make things clearer. But Simons-Morton says this is the first totally【C20】______look at teen driver distraction.

【C1】

A．start over

B．start for

C．start off

D．come off