Given the structures of A, B and C in the following reactions :
(i) `CH_(3) Br overset (KCN) toAoverset(LilH_(4))to B overset(HNO_(2))underset(273k)toC`
(ii) `CH_(3) COOH overset (NH_(3))undersetDelta toAoverset(Br_(2)+KOH)to B overset(CHCL_(3)+NaOH)toC`

Explanation

To solve the problem, we will go through each reaction step-by-step to identify the structures of A, B, and C.

### Reaction (i):
1. **Starting Material**: CH₃Br (Methyl Bromide)
- This is an alkyl halide.

2. **Reaction with KCN**:
- When CH₃Br reacts with KCN, the bromine atom is replaced by a cyanide group (CN).
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