Answer:
A. carbon and oxygen
Step-by-step explanation:
They indicate the number of each chemical species that reacts or is formed. Methane and oxygen (oxygen is a diatomic — two-atom — element) are the reactants, while carbon dioxide and water are the products.
This is because it states, "To form," which means that it was produced from the reactants Carbon and Oxygen.
To know what the products are in a statement rather than an equation, words such as produced and formed are used.
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