When interpreted literally, the source text indicates that the top note in the trill is c2, since there is no accidental clarifying its pitch. However, Chopin frequently omitted such accidentals (cf., e.g. bar 23 and 93 or the Scherzo in B minor, Op. 31, bar 74), hence it is not entirely certain whether this was indeed his intention. The use of an e-d seventh to write down the diminished four-note chord naturally implies c2, which is confirmed by the key of F minor, valid for the next 16 bars. Nevertheless, this is not a decisive argument, since the discussed bar is of a transitional nature, while the used chords, allowing a variety of interpretations, do not determine the key.
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category imprint: Interpretations within context; Editorial revisions
notation: Ornaments