请选择CBA4i9S,g2}0D1]*V,m6M3C2@1K-i,o7H We ___ at the airport all morning before there was any news about our flight.;{.b'_1G6|1A1c2F4l
A. have been waiting;{.b'_1G6|1A1c2F4l
B. had been waiting;{.b'_1G6|1A1c2F4l
C. are waiting;{.b'_1G6|1A1c2F4l