The correct option is C CrO3/Acetone/H2O
Because acyclic ketones are relatively stable to Cr(VI) oxidations, acetone is frequently used as the solvent for Cr(VI) oxidations of alcohols. In these reactions, a CrO3/H2SO4/H2O mixture is slowly added to an acetone solution of the alcohol, or the alcohol is mixed with an acetone solution of CrO3/H2SO4/H2O.