What scale has the same notes as its relative major scale but begins on a different tonic?

The natural minor scale is indeed the correct choice here because it is constructed from the same notes as its relative major scale, but it begins on a different tonic. For example, the A natural minor scale uses the same notes as the C major scale (A, B, C, D, E, F, G), but it centers around A as the tonic. This relationship between the natural minor and its relative major scale is a foundational concept in music theory, demonstrating the duality within scales that share the same key signature.

In contrast, the harmonic minor scale introduces raised seventh degrees compared to its relative major, thereby altering the note set and distinguishing it from the natural minor. The melodic minor scale also modifies the sixth and seventh degrees when ascending, and changes again when descending, which does not preserve the same note collection as its relative major. Lastly, the chromatic scale consists of all twelve pitches within an octave, without adhering to the structure that links the major and minor scales. Thus, the natural minor scale maintains the fundamental relationship with its relative major most clearly.