An Astute Physics Student Is near a Train Track

Multiple Choice

An astute physics student is near a train track. As a train speeds by, the perceived frequency of the whistle changes from middle C to the A below middle C. If the initial perceived frequency of the whistle had been an octave above middle C, as the train whizzed by the frequency would have changed to

A) the A above middle C.
B) a frequency > the A above middle C.
C) a frequency < the A above middle C.
D) none of the above.