Which mode is major scale with raised fourth?

• A. Ionian
• B. Mixolydian
• C. Lydian
• D. Aeolian

Answer: (C)

Raising the fourth degree of the major scale creates the Lydian mode. In the major scale, the fourth note is the subdominant. If you sharpen that note, you get a scale with an augmented fourth, which gives a distinct bright, dreamy color characteristic of Lydian. For example, in C, the major scale is C D E F G A B C; raising the fourth turns F into F#, yielding C D E F# G A B C—this is C Lydian. The other modes involve different alterations: Ionian is the ordinary major scale with no raised notes; Mixolydian lowers the seventh; Aeolian is the natural minor. So the mode described as the major scale with a raised fourth is Lydian.