The missing , clarifying that it is the c3 major second, and not the c3 augmented second, that should be used as the top mordent note, is probably an inaccuracy by Chopin, who only occasionally clarified the pitch of auxiliary notes in ornaments with an accidental. In spite of c3, played a moment ago, the default choice in a descending minor scale is a natural seventh, in this case c3 in the D minor scale. However, it does not mean that there are no exceptions to this rule, hence the literal interpretation of the text may be regarded as an acceptable variant, particularly since the use of augmented seconds in the melody of the two previous bars may mean that the composer wanted to achieve peculiar timbre of the minor version of this phrase with the help of those intervals.
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category imprint: Editorial revisions
issues: Omission of current key accidentals
notation: Ornaments