Salt (A) gives brick red fumes (B) with conc. H2SO4 and K2Cr2O7 which gives yellow solution (C) with — Qualitative and Quantitative Analysis Chemistry Question

Question

Salt (A) gives brick red fumes (B) with conc. H2SO4 and K2Cr2O7 which gives yellow solution (C) with NaOH and it gives yellow ppt. (D) with acetic acid and lead acetate. What is (C)?