Answer :
Final answer:
To generate a pitch an octave higher on a violin, one must shorten the vibrating length of the string (Option B). This change in length doubles the frequency of the note being played, which results in an octave-higher pitch.
Explanation:
To generate a pitch an octave higher on a violin, one must shorten the vibrating length of the string. This is because the frequency of the note produced by a string is inversely proportional to the length of the vibrating string, as per the physics of string instruments.
When the length of the vibrating portion of the string is shortened, its frequency doubles, resulting in a pitch that is one octave higher. Shortening the string is often accomplished by pressing down on the string at the appropriate point with a finger, effectively reducing its vibrating length.
The other options listed, such as 'pressing the string harder' or 'using a thicker string,' would not yield an octave higher pitch. Pressing harder increases volume due to the increased frictional force (W = Fd), while a thicker string would affect the timbre and possibly the pitch, but not specifically raise it by an octave.