The motor vehicle has killed and disabled more people in its brief history than any bomb or weapon ever invented. Much of the blood on the street flows essentially from uncivil behaviour of drivers who refuse to respect the legal and moral rights of others. So the massacre on the road may be regarded as a social problem.
In fact, the enemies of society on wheels are rather harmless people—just ordinary people acting carelessly, you might say. But it is a principle both of law and common morality that carelessness is no excuse when one's actions could bring death or damage to others. A minority of the killers go even beyond carelessness to total negligence(疏忽).
Researchers have estimated that as many as 80% of all automobile accidents can be attributed to the psychological condition of the driver. Emotional upsets can distort drivers' reactions, slow their judgment, and blind them to dangers that might otherwise be evident. The experts warn that it is vital for every driver to make a conscious effort to keep one's emotions under control.
Yet the irresponsibility that accounts for much of the problem is not confined to drivers. Street walkers regularly violate traffic regulations, they are at fault in most vehicle-walker accidents, and marty cyclists even believe that they are not subject to the basic rules of the road.
Significant legal advances have been made toward safer driving in the past few years. Safety standards for vehicle have been raised both at the point of manufacture and through periodic(定期的)road-worthiness inspections. In addition, speed limits have been lowered. Due to these measures, the accident rate has decreased. But the accident experts still worry because there has been little or no improvement in the way drivers behave. The only real and lasting solution, say the experts, is to convince people that driving is a skilled task requiring constant care and concentration. Those who fail to do all these things present a threat to those with whom they share the road.

【正确答案】 B

【答案解析】由题干中的psychological conditionof the drivers定位至第三段。该段首先给出具体数据说明80％的摩托车交通事故是由于驾驶员的心理状况所导致的，情绪不安扰乱了驾驶员的反应，减慢了其判断。接着引用专家的警告指出，对于任何一名驾驶员，保持情感和心态处于可控状态至关重要，由此得出作者提及该话题的目的是B)。