Which of the following statements regarding chronic bronchitis are TRUE:

A、Chronicbronchitisisdefinedaspersistentproductivecoughforatleast3consecutivemonthsinatleast2consecutiveyears
B、Cigarettesmokingisthemostimportantriskfactor
C、Airpollutantscontributetochronicbronchitis
D、Thedominantpathologicfeaturesaremucushypersecretionandpersistentinflammation
E、Histologicexaminationdemonstratesenlargementofmucous-secretingglands,gobletcellhyperplasia,chronicinflammation,andbronchiolarwallfibrosis