单选题：First Aid　　First aid is emergency care for a victim of sudde

First Aid　　First aid is emergency care for a victim of sudden illness or injury until more skillful medical treatment is available. It may save a life or improve certain vital signs including pulse, temperature, a clear airway (气道), and breathing. In minor emergencies, first aid may prevent a victim's condition from turning worse and provide relief from pain. First aid must be administered as quickly as possible. In the case of the critically injured, a few minutes can make the difference between complete recovery and loss Of life.
　　First-aid measures depend upon a victim's needs and the provider's level of
knowledge and skill. Knowing what not to do in an emergency is as important as knowing　what to do. Improperly moving a person with a neck injury, for example, can lead to permanent spinal (脊柱的) injury and paralysis (瘫痪).
Despite the variety of injuries possible, several principles of first aid apply to all emergencies. The first step is to call for professional medical help. The victim, if conscious, should be reassured that medical aid has been requested, and asked for permission to provide any first aid. Next, assess the scene, asking other people or the injured person's family or friends about details of the injury or illness, any care that may have already been given, and preexisting conditions such as diabetes (糖尿病) or heart trouble, The victim should be checked for a medical bracelet (手镯) or card that describes special medical conditions. Unless the accident scene becomes unsafe or the victim may suffer further injury, do not move the victim.First aid requires rapid assessment of victims to determine whether life-threatening conditions exist. One method for evaluating a victim's condition is known by the acronym (首字母缩写词) ABC, which stands for:
A - Airway: is it open and clear?
B - Breathing: is the person breathing? Look, listen, and feel for breathing.
C - Circulation: is there a pulse? Is the person bleeding externally? Check skin color and temperature for additional indications of circulation problems.First aid may bring about all the following results EXCEPT A．saving a victim's lif
B．preventing a victim's condition from getting wors
C．helping a person avoid sudden illness or injur
D．relieving a victim from pai