“三凹征”指的是
A.胸骨上窝、锁骨上窝、肋间隙在呼气时明显下陷
B.胸骨上窝、锁骨下窝、肋间隙在呼气时明显下陷
C.胸骨上窝、锁骨上窝、肋间隙在吸气时明显下陷
D.胸骨上窝、锁骨上窝、腹部在呼气时明显下陷
E.胸骨上窝、锁骨下窝、腹部在吸气时明显下陷
正确答案是C