Which scale degrees form a major triad?

Which scale degrees form a major triad?

• A. 1, 4, 5
• B. 2, 3, 6
• C. 1, 3, 5
• D. 1, 2, 5

Answer: (A)

A major triad occurs when the root, a major third above, and a perfect fifth above are all available in the scale. In a diatonic major scale, that pattern yields major triads on scale degrees 1, 4, and 5. For example, in C major those are C-E-G, F-A-C, and G-B-D. Triads built on degrees 2, 3, and 6 come out minor (D-F-A, E-G-B, A-C-E), and the triad on degree 7 is diminished (B-D-F). So the scale degrees that form a major triad are 1, 4, and 5.

A major triad occurs when the root, a major third above, and a perfect fifth above are all available in the scale. In a diatonic major scale, that pattern yields major triads on scale degrees 1, 4, and 5. For example, in C major those are C-E-G, F-A-C, and G-B-D. Triads built on degrees 2, 3, and 6 come out minor (D-F-A, E-G-B, A-C-E), and the triad on degree 7 is diminished (B-D-F). So the scale degrees that form a major triad are 1, 4, and 5.