A recent study offers a picture of how dangerous it is to get a lift from a teenage driver

A recent study offers a picture of how dangerous it is to get a lift from a teenage driver. Indeed, a 16-year-old driver with three or more passengers is three times as likely to have a fatal（致命的）accident as a teenager driving alone. However, the possibility of death for drivers between 30 and 59 decreases with each additional (added) passenger.
　　It was also found that the death rates for teenage drivers increased greatly after 10 p.m., and especially after midnight. With passengers in the car, the driver was even more likely to die in a late night accident.
　　Robert Foss, a scientist at the University of North Carolina Highway Safety Research Center, says the higher death rates for teenage drivers have less to do with “really stupid behavior” than with just a lack of driving experience. Both he and the author of the study believe that the way to help solve the problem is to have states setting up so-called graduated licensing systems（等级执照制）. A graduated license requires that a teenager first prove that he/she is able to drive in the presence of an adult, followed by a period of driving with a limited number of passengers, before graduating to full driving on his own. About half of the states now have some sort of graduated licensing system in place. The systems have reduced teenage driver crashes（相撞）, according to recent studies.
【小题1】Which of the following situations is most dangerous according to the passage?A．Adults giving a lift to teenagers on the highway after 10 p.m.B．A teenager driving after midnight with passengers in the car.C．Adults driving with three or more teenage passengers late at night.D．A teenager getting a lift from a stranger on the highway at midnight.【小题2】According to Robert Foss, the high death rate of teenage drivers is mainly because     .A．their preference for driving at nightB．their lack of driving experienceC．their careless way of drivingD．their driving with passengersB