Identify the type of chemical reaction: 

$2Na\left(s\right)\mathit{+}S\left(s\right)\to N{a}_{2}S\left(s\right)$

Combination reactions are the type of redox reactions in which two small molecules combine into one larger molecule. In the given reaction, sodium and sulfur are combined to give sodium sulfide. It is a combination reaction. Combination reactions are prevalent in many natural oxidation processes. Likewise, examples of combination reactions are those in which the reactants include metals and halogens. Halogens or oxygen can provide suitable anions, while metals can create suitable cations. As a result, it is also frequently seen that combination reactions are ionic reactions. Different metals and reactive non-metals, such as halogens, can create these reactions. Other instances of covalent bonding include the synthesis of sulfur dioxide from the reaction of sulfur and oxygen.

Hence, option C is correct.