What distinguishes string family instruments?

The distinguishing characteristic of string family instruments is that they produce sound through the vibration of strings that are typically stretched across a wooden body. These instruments are often played with a bow, which causes the strings to vibrate, resulting in sound production. This mechanism of sound creation is fundamental to strings instruments such as violins, cellos, and double basses, highlighting the importance of the strings' vibration in the overall function of the instrument.

Other options relate to different families of instruments: instruments that vibrate air columns pertain to woodwinds and brass; those characterized by metal construction are often found in percussion instruments; and those played by striking surfaces or shaking describe percussion instruments as well. Therefore, while these other options refer to valid characteristics in their respective families, they do not apply to the unique feature defining string family instruments.