Final answer:
The reaction described, where a nucleophile attacks and replaces the iodide group in (R)-2-iodo-4-methylpentane, is a nucleophilic substitution reaction.
Step-by-step explanation:
The (R)-2-iodo-4-methylpentane alkyl halide is a substrate for which a nucleophile can attack and replace an existing group - in this case, the iodide group. This describes a nucleophilic substitution reaction. Such reactions involve a nucleophile attacking the electrophilic center of a substrate and displacing a leaving group. The result of this reaction is an inversion of stereochemistry due to the mechanism taking place in a single, concerted step. When looking at the given options for the reaction type, the correct answer is A) Substitution reaction. Nucleophilic substitution reactions such as SN1 or SN2 mechanisms are common for alkyl halides like the one described in the question.