In A before the 2nd demisemiquaver in the 3rd group, one can see a crossing-out, most probably of a 
lowering it to c
3. It would confirm that Chopin was convinced that accidentals before the 2nd and 8th demisemiquavers in each group are not necessary, since their pitch is determined by the preceding note, placed an octave lower. Similarly in the Prelude in E no. 19, bar 13 and 39.
Compare the passage in the sources »
category imprint: Corrections & alterations; Source & stylistic information
issues: Corrections in A, Errors resulting from corrections, Deletions in A
notation: Pitch