The ATS unit must ensure that pilots are kept informed of any change in the status of airport facilities（ ）.
A.at their destinations
B.at their alternate aerodromes
C.at their destinations and at their alternate aerodromes
正确答案是C
The ATS unit must ensure that pilots are kept informed of any change in the status of airport facilities（ ）.
A.at their destinations
B.at their alternate aerodromes
C.at their destinations and at their alternate aerodromes
正确答案是C