Which choice lists the structures adapted for permitting air flow from the external environment to the human lungs in the correct order? a) nasal cavity, bronchi, bronchioles, pharynx, trachea b) nasal cavity, trachea, pharynx, bronchi, bronchioles c) nasal cavity, pharynx, trachea, bronchi, bronchioles d) nasal cavity, bronchioles, trachea, pharynx, bronchi