Write a chemical equation, clearly showing the stereochemistry of the starting material and the product, for the reaction of (S)−1−bromo−2−methylbutanewith sodium iodide in acetone

(S)−1−iodo−2−methylbutane

Explanation:

This reaction involves the substitution of iodine for bromine in (S)−1−bromo−2−methylbutane. The reaction proceeds with retention of configuration because the product is (S)−1−iodo−2−methylbutane. There is no change in the configuration of the product compound when the reaction is carried out in acetone which is a polar aprotic solvent. The reaction is shown in the image attached.

i think that the answer is c