Match List-I with List-II.List-IList-II(A) An ambident nucleophile(I)…

The correct answer is Option (3) → A-III, B-I, C-IV, D-II

(A) An ambident nucleophile — This matches (III) Cyanide ion. The cyanide ion has two nucleophilic centres: it can link through carbon, giving an alkyl cyanide, or through nitrogen, giving an isocyanide.

(B) The leaving group when hydroxide ion reacts with bromoethane — This matches (I) Bromide ion. The hydroxide ion replaces the halogen, which departs as a halide ion:

    \( \displaystyle \ce{C2H5Br + OH^- -> C2H5OH + Br^-} \)

(C) A polar protic solvent in which S_N1 reactions are carried out — This matches (IV) Acetic acid. Water, alcohol and acetic acid are the polar protic solvents in which S_N1 reactions are generally carried out.

(D) The solvent in which alkyl chlorides are converted into alkyl iodides with NaI — This matches (II) Dry acetone. This is the Finkelstein reaction; the NaCl formed is precipitated in dry acetone, which drives the reaction forward:

    \( \displaystyle \ce{R-Cl + NaI} \xrightarrow{\text{dry acetone}} \ce{R-I + NaCl} \)

NCERT (2026-27 edition):
6.7.1 Reactions of Haloalkanes – “…A substitution reaction takes place and halogen atom, called leaving group departs as halide ion.” … “Groups like cyanides and nitrites possess two nucleophilic centres and are called ambident nucleophiles. Actually cyanide group is a hybrid of two contributing structures and therefore can act as a nucleophile in two different ways … i.e., linking through carbon atom resulting in alkyl cyanides and through nitrogen atom leading to isocyanides.” … “S_N1 reactions are generally carried out in polar protic solvents (like water, alcohol, acetic acid, etc.).”

6.4.3 Halogen Exchange – “Alkyl iodides are often prepared by the reaction of alkyl chlorides/ bromides with NaI in dry acetone. This reaction is known as Finkelstein reaction. NaCl or NaBr thus formed is precipitated in dry acetone. It facilitates the forward reaction according to Le Chatelier’s Principle.”