Harmony is an essential musical element that plays a significant role in improvisation. It refers to the combination of chords and their progression in a piece of music. Hence option D is correct .
Which musical elements is usually not altered for improvisation?While improvisation often involves experimenting with different notes and chords, it is not uncommon for musicians to alter the harmony as well. In fact, harmony can be one of the most flexible elements to manipulate during improvisation.
Musicians can alter the harmony in a variety of ways to create new and interesting sounds. For example, they might add or substitute chords to create tension and release or to change the overall mood of the music. They might also change the chord progression, add embellishments, or use extended chords to add complexity to the harmony.
That being said, it is important to note that improvisation is a creative process, and there are no hard and fast rules about what can and cannot be altered. Ultimately, the decision to alter any musical element, including harmony, is up to the individual musician and their artistic vision for the piece.
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