What you really need to know is how to identify all of the basic reaction types. Each has a distinctive format that makes it easy.
1. synthesis (combination) .... only one product
2. decomposition .... only one reactant
3. single replacement .... element + compound --> element + compound
4. double replacement .... two compounds on each side, where (a) there is the formation of a precipitate, or (b) there is an acid/base reaction (usually a simple Arrhenius A/B reaction).
5. complete combustion of a hydrocarbon .... hydrocarbon burns in O2 to make CO2 and H2O
Of your choices, only (D) has a single reactant, and it is the decomposition reaction. Just because some are balanced, doesn't help you identify the reaction type.
You can find general descriptions of these at my website, along with a sample worksheet.