You are crossing a narrow channel in a 15-meter vessel when you sight a tanker off your port bow coming up the channel. Which statement is TRUE? （）

A. Yours is the give-way vessel because it is less than 30 meters long
B. You shall not impede the safe passage of the tanker
C. The tanker is the stand-on vessel because it is to port of your vessel
D. The tanker is the stand-on vessel because it is the larger of the two vessel