Is the classification for an instrurment that produces sound by the vibration of a colurnn of air.
OA Idiophone
OB. Chordophone
OC. Aerophone
OD. Menbranophone

C. Aerophone

Explanation:

Aerophone instruments are those with which sound is produced by the vibrating air. They do not have additional strings or membranes and they are one of the main classes of instruments.

They are divided into free and non-free.

Free aerophone is those where the air is not inside of the instrument, but out and the air vibration is just made by the instrument.

Non-free, also known as wind instruments, are those where the air is vibrating inside the instruments. These are the most commonly used today, especially in the orchestras. Instruments like the flute, clarinet, horn, piccolo, saxophone, trumpet, etc. are all non-free aerophone instruments commonly used today.