One mole of an alkanol and one mole of an alkanal, each containing n moles of carbon atoms in its molecule, was separately combusted in excess oxygen. The volumes of steam produced by the compounds were in ratio 5:4. What are the respective formulae of the compounds?

• A.C₄H₉OH and C₄H₇CHO
• B.C₄H₉OH and C₃H₇CHO
• C.C₃H₇OH and C₃H₇CHO
• D.C₄H₉OH and C₄H₉CHO