• It depends on what exactly is meant by tonality and key. The key signature says A major.

But A is not the key note in this piece. You can't play the chord of A at the end, as you can with classic pieces in A:

With E as key note it would be E mixolydian: e f# g# a b c# d e. Norwegian Wood of The Beatles is in E mixolydian. Here is a piece in E mixolydian:

The E doesn't really feel like being the key of the piece. Does it? I prefer to conclude that this kind of music just work with chords in stead of scales because there is no keynote anymore.