Which of the following is combustion reaction

When all substances in a compound combine with oxygen and produces CO2 and H2O, it is commonly called burning. During combustion substance reacts with an oxidizing agent such as O2 and F2 . Not all combustion reaction releases CO2 and  H2O     e.g.Mg+O2→MgO+Heat.∴3.2gm will liberate =890×3.216=178kJ.