Which of the following is NOT a type of musical scale?

The classification of musical scales is vital for understanding music theory. The harmonic scale, as described, actually refers to specific harmonic structures rather than a type of scale that is commonly categorized alongside terms like pentatonic, whole tone, and major scales.

Pentatonic scales consist of five notes and are widely used across various musical traditions. Whole tone scales are built entirely of whole steps, creating a unique sound distinct from other scale types. Major scales, consisting of seven notes with a specific pattern of whole and half steps, are fundamental in Western music.

In contrast, while "harmonic" might suggest a relationship to harmony or even the harmonic minor scale, it does not represent a standalone scale type in the same context as the other options. As a result, the identification of harmonic as not being a distinct musical scale makes it the correct answer in this question.