AIIMS 2018 Chemistry S_N2 Reactions MCQ Question

Option A represents the product of an S_N₂ substitution reaction, where the nucleophile attacks the electrophile from the opposite side of the leaving group, resulting in Walden inversion. This inversion leads to a configuration change, making the product's stereochemistry the opposite of the reactant. Other options (B, C, D) likely depict configurations that do not reflect the inversion process characteristic of S_N₂ reactions, where the stereochemical outcome must be inverted relative to the starting material. Understanding this mechanism is crucial for predicting the stereochemical outcomes in nucleophilic substitution reactions.