K331 Var II Question

[schneid]

This may seem like a silly question, but in the 2nd Var of Mozart's Sonata in A, the left hand plays D sharp- while the right hand plays D natural?! It seems quite dissonant for Mozart, but with no accidentals in the treble staff I assume this is correct. If anyone could confirm/clarify my confusion...

[kalirren]

It's not a silly question.  Your score is correct.  The D in the right hand comes from the melody being in the key of A.  The D-sharp in the left hand comes from being the leading tone, and later grace note, to the E, just like all the other grace notes in the left hand are only a half step from their principal notes.