Answer: decomposition
Explanation:
1 . Combustion is a type of chemical reaction in which a hydrocarbon reacts with oxygen to form carbon dioxide ans water along with liberation of large amount of energy.
2. Decomposition is a type of chemical reaction in which a single reactant gives two or more than two products.
3. Single replacement is a type of chemical reaction in which a more reactive element displaces the less reactive element from its slat solution.
4. Synthesis is a type of chemical reaction in which two or more than two reactants combine together to give a single product.