JAMB - Physics (1992 - No. 19)
A note is the octave of another note if it has
a frequency twice that of the first note
frequency half that of the first note
the same fundamental frequency as the first one
a frequency frequency eight times that of the first note
Explication
When the frequency of a note is doubled, it is perceived as being one octave higher. For example, if a note has a frequency of fff, the note one octave higher will have a frequency of 2f. Conversely, a note that is one octave lower has a frequency half that of the original note, but the question specifically asks for the octave above