I think it is C.
hope this helps
plz mark brainliest if correct
Answer: Cowell
Explanation:
The first one who experimented with piano strings and clusters is Henry Cowell.
He was the first one who asked the pianist to manipulate string and then when he discovered the sound.
Before that new sound, he discovered also <u>tone clusters</u>. Tone clusters were achieved by hitting the piano keys with elbows or fists.