The correct group of halide ions which can be oxidised by oxygen in acidic medium is:
\( \mathrm{Cl^-} \), \( \mathrm{Br^-} \) and \( \mathrm{I^-} \) only
\( \mathrm{I^-} \) only
\( \mathrm{Br^-} \) and \( \mathrm{I^-} \) only
\( \mathrm{Br^-} \) only