Step 1: Reaction with sodium nitrite.
Sodium salt of $\alpha$-halogen carboxylic acid reacts with sodium nitrite to undergo nucleophilic substitution, replacing the halogen atom with a nitro group.
Step 2: Hydrolysis step.
On hydrolysis, the intermediate compound rearranges to form a nitroalkane.
Step 3: Elimination of other options.
This reaction does not produce amines, alcohols, or amides under the given conditions.
Step 4: Conclusion.
Therefore, the final product obtained is nitroalkane.