人在吸气时，膈肌和肋间外肌的生理活动是（ ）
A．膈肌收缩，肋间外肌舒张
B．膈肌舒张，肋间外肌收缩
C．膈肌舒张，肋间外肌舒张
D．膈肌收缩，肋间外肌收缩
吸气时，膈肌与肋间肌收缩，引起胸腔前后、左右及上下径均增大，肺随之扩大，造成肺内气压小于外界大气压，外界气体进入肺内，形成主动的吸气运动；呼气时，膈肌和肋间外肌舒张，肋骨与胸骨因本身重力及弹性而回位，结果胸廓缩小，肺也随之回缩，造成肺内气压大于外界气压，肺内气体排出肺，形成被动的呼气运动．因此人在吸气时，膈肌和肋间外肌的生理活动是膈肌收缩，肋间外肌收缩．
故选：D
完形填空 I have a nice family. Only 26 people are in it. They’re my 27 , my mother and me. Here is a 28 of my family. This is my father. He likes dogs (狗) and he has a white 29 . The name of it is Tony. Look! Tony is next to (挨着) my father 30 the photo. Look at my mother. She 31 to cook (烹调). She cooks 32 food for us every day. This is me. I’m 11. I’m in a good 33 . I like English and our English classes are 34 . I like playing sports and I like 35 sports games on TV. My family is nice and I like it.
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