A.喉腔較窄 B.聲門裂狹窄 C.軟骨柔軟 D.粘膜柔嫩富有血管 E.淋巴組織較少
A.600~720ml B.720~900ml C.900~1000ml D.900~1080ml E.1000~1200ml
A.25% B.33% C.50% D.60% E.80%