[单选题]

---What should I do first before boarding? ----().
A．You may ask the policeman there to help.
B．Please go to the airline counter to check-in for your flight.
C．You should wait and see.
D．You have to go there to check in for your flight.

---What should I do first before boarding? ----().A．You may ask the policeman there to help.B．Please go to the airline counter to check-in for your flight.C．You should wait and see.D．You have to go there to check in for your flight.