b. 7
When interpreted literally, the chord on the 3rd beat of the bar in A (→FC) consists of the following notes: F1-F-b-d1-f1, which, in turn, results in a G major chord (F major), which could be a part of this harmonic sequence. However, Chopin would generally avoid such an unnatural orthography; therefore, he most probably overlooked here the naturals lowering all f notes to f. They were added both in FE (→EE) and GE, and the composer did not question the printed naturals in any of the three teaching copies containing annotations coming from him.
Compare the passage in the sources»
category imprint: Interpretations within context; Differences between sources
issues: GE revisions, Omission of current key accidentals, Errors of A, FE revisions
notation: Pitch