air entering lungs is
1 warmed
2 filtered
3 deprived of o2
4 enriched with co2
which is true?
1 and 2
all
2 and 4
2 and 3
explain reason

 

air enterng lungs in the sense it is inspiration. hence air entering lungs is enriched with po2 and deprived with pco2, hence we can reject following  options: all, 2 and 4 , 2 and 3 . hence conducting part brings inspired air to the body temperature. hence air inspired is warmed and filteredby mucus lining in nostrils hence i guess by trial and error method the answer could be 1 and 2.