Correct Answer - A
Oxalic acid is formed by oxidation of ethylene glycol with acidified potassium dichromate.
`{:(CH_(2)OH " "COOH),(|" "+4[O]underset(H_(2)SO_(4))overset(K_(2)Cr_(2)O_(7))to |" "+2H_(2)O),(underset("Ethylene glycol")(CH_(2)OH)" "underset("Oxalic acid")(COOH)):}`