Two sequences are carried out on bromoethane. Sequence I: $\mathrm{KCN}$ in aqueous ethanol, then boiling with dilute $\mathrm{HCl}$. Sequence II: $\mathrm{AgCN}$ in ethanol (covalent, N-bonded reagent), then warming with dilute $\mathrm{HCl}$. Select the correct statements.

1. AIn sequence I the nitrogen atom of cyanide is the nucleophilic site that bonds to the ethyl carbon.
2. BSequence I finally gives propanoic acid (as ammonium chloride is also formed).
3. CSequence II finally gives propanoic acid, since both cyanide reagents form a C-C bond.
4. DSequence II finally gives ethylammonium chloride and methanoic (formic) acid.