Both SN2 and E2 reactions are stereospecific. However, E2 elimination with anti-periplanar geometry is classically cited as the stereospecific example — the leaving group and the \(\beta\)-hydrogen must be anti-periplanar (180°). This strict geometric requirement means only specific stereoisomers of the substrate produce specific stereoisomers of the product. SN2 also shows inversion (Walden inversion), making it stereospecific too, but option (C) is the most precise answer as written.