50. In negative-pressure breathing, inhalation results from
(A) using muscles of the lungs to expand the alveoli.
(B) relaxing the muscles of the rib cage.
(C) contracting the diaphragm.
(D) contracting the abdominal muscles.
(E) forcing air from the throat down into the lungs.
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統計: 尚無統計資料
統計: 尚無統計資料