When a station officer is guiding passengers to pass the ticket gates，what should he or she do?

A、Ifaveryoldladycomes,heorsheshouldadvisehertostayclosetohisfamilyorhelpherpassthegateandgodowntheplatform.;
B、Ifapassengeriseatingandpassingthegateatthesametime,heorsheshouldcomeuptostopthepassengerandexplaintohimthatnoeatinganddrinkingallowedinthesubway.;
C、Ifapassengerinwheelchairscomes,heorsheshouldadvisehimtotaketheliftforhissafety.;
D、Ifalotofpassengersgatherattheticketgate,heorsheshouldguidethepassengerstoformlinesandtouchinonebyone.