Listen to the melody again and consider which pitch, C or F, sounds more stable-in other words, which pitch sounds more restful, more like a musical destination and less like an attraction along the way. To determine the key of this melody-C major or F major-we need to decide which note sounds most like the tonic.

But all of these pitches also belong to the F major scale (F, G, A, B b, C, D, and E). This is a very good indication that this melody is in the key of C major. All of these pitches belong to the C major scale (C, D, E, F, G, A, and B). As you can see, this melody uses the pitches C, D, E, F, G, and A.