问题
单项选择题
The least serious form of brain trauma, characterized by a brief loss of consciousness and period of confusion, is called（）
A. contusion.
B. concussion.
C. coup.
D. contrecoup.
答案
参考答案：B
解析：
Concussions are considered minor with no structural signs of injury. A contusion is bruising of the brain tissue with small hemorrhages in the tissue. Coup and contrecoup are types of injuries in which the damaged area on the brain forms directly below the site of impact (coup) or at the site opposite the injury (contrecoup) due to movement of the brain within the skull.