Concept:Lucas reagent is a specific mixture used to test the reactivity of alcohols.
Explanation:Lucas reagent is prepared by dissolving anhydrous zinc chloride in concentrated hydrochloric acid.
Its chemical composition is conc.
HCl+ZnCl2.
It is used to distinguish primary, secondary, and tertiary alcohols.
Tertiary alcohols react immediately, secondary alcohols react slowly, and primary alcohols do not react at room temperature.
This difference occurs due to the stability of the carbocation intermediate formed.
Thus, among the given options, only option A represents Lucas reagent.
Answer:A. Conc.
HCl+ZnCl2