[单选题]航空器必须在指定的无线电频率上与空中交通管制部门联络并接受管制。 A.All aircraft shall establish contact with the ATC department on the appointed radio frequencies and accept its control B.All aircraft shall establish contact with the ATC department in the appointed radio frequencies and accept its control C.All aircraft shall establish contact with the ATC department on the assigned radio frequencies and accept its control D.All aircraft shall establish contact with the ATC department in the assigned radio frequencies and accept its control