Multiphonics are an example of what technique

A multiphonic is an extended technique on a monophonic musical instrument (one which generally produces only one note at a time) in which several notes are produced at once. This includes wind, reed, and brass instruments, as well as the human voice. Multiphonic-like sounds on string instruments, both bowed and hammered, have also been called multiphonics, for lack of better terminology and scarcity of research.

1) d2) a3) false  4) true  5) false

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