What type of instruments are categorized as friction idiophones?

Friction idiophones are a unique category of instruments that produce sound specifically through the action of rubbing. This technique involves the friction created when a stick or another object is drawn across the surface of the instrument, which can cause it to vibrate and thus create sound. Instruments like the musical saw, where a bow is drawn across the edge, or the nail violin, fall into this category.

The other options describe different families of instruments: instruments that produce sound by shaking refer to shaking idiophones like maracas, ones played by striking refer to percussion instruments like drums or cymbals, and those that generate sound through airflow are classified as wind instruments, such as flutes or clarinets. Each category has a distinct method of sound production, but friction idiophones uniquely rely on the act of rubbing to create their sound.