Answer: The correct answer is Option A.
Step-by-step explanation:
In a chemical equation, the chemical species are termed as reactants or products.
Reactants are defined as the species which react in the reaction and are written on the left side of the reaction arrow.
Products are defined as the species which are produced in the reaction and are written on the right side of the reaction arrow.
For the given chemical equation:

The chemical species written on the left side of the arrow are
. They are considered as reactants.
The chemical species written on the right side of the arrow are
. They are considered as products
Hence, the correct answer is Option A.