What does the term "perfect interval" refer to in music?

The term "perfect interval" refers to consonant intervals recognized by music theory, which encompasses particular relationships between pitches. In Western music, perfect intervals include the perfect unison, perfect fourth, perfect fifth, and perfect octave. These intervals are characterized by their stability and consonance, providing a sense of resolution and openness in musical contexts. This quality distinguishes them from other intervals that might evoke tension or require resolution, such as dissonant intervals.

Understanding that perfect intervals are fundamental to building harmonies and chords is crucial in music composition and analysis. This foundation provides musicians and composers with the tools to create effective and pleasing harmonic progressions, making option B accurate in defining perfect intervals within music theory.