Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): $$\alpha$$-halocarboxylic acid on reaction with dil. NH$$_3$$ gives good yield of $$\alpha$$-amino carboxylic acid whereas the yield of amines is very low when prepared from alkyl halides.
Reason (R): Amino acids exist in zwitter ion form in aqueous medium.
In the light of the above statements, choose the correct answer from the options given below:

We need to evaluate the Assertion and Reason about amino acid synthesis.

Assertion: $$\alpha$$-halocarboxylic acid on reaction with dilute NH$$_3$$ gives good yield of $$\alpha$$-amino carboxylic acid, whereas the yield of amines is very low when prepared from alkyl halides.

This is correct. When alkyl halides react with NH$$_3$$, the product amine is more nucleophilic than NH$$_3$$ itself, leading to over-alkylation (polyalkylation) and low yield of primary amine. However, $$\alpha$$-halocarboxylic acids give good yield of amino acids because the product amino acid exists as a zwitter ion, which is much less nucleophilic than NH$$_3$$, preventing further reaction.

Reason: Amino acids exist in zwitter ion form in aqueous medium.

This is correct. Amino acids exist as $$^+\text{NH}_3\text{-CHR-COO}^-$$ in aqueous medium.

The reason (R) does explain the assertion (A). The zwitter ion form makes the amino group in the product positively charged ($$-\text{NH}_3^+$$), so it cannot act as a nucleophile to undergo further alkylation. This is why the yield is good for amino acid synthesis but poor for amine synthesis from alkyl halides.

Therefore, both (A) and (R) are correct, and (R) is the correct explanation of (A).

The correct answer is Option A: Both (A) and (R) are correct and (R) is the correct explanation of (A).