(来学网)正常人生理死腔的通气占肺通气量的比为 ( )
  • A.
    (来学网)20%
  • B.
    (来学网)30%
  • C.
    (来学网)40%
  • D.
    (来学网)15%
  • E.
    (来学网)30%~40%