Identify A, B, C and D in the following conversions:
`A underset(0-5^(@)C)overset(NaNO_(2)//HCl)(to) CH_(3)OH overset(PCl_(3))(to) B overset(KCN)(to) C overset(LiAIH_(4))(to) D`

Explanation

To solve the problem step by step, we need to identify the compounds A, B, C, and D based on the given conversions and reagents.

### Step 1: Identify Compound A
The first part of the conversion involves treating an amine with NaNO₂ and HCl at low temperatures (0-5°C). This reaction is characteristic of primary amines, which are converted into alcohols. Since the final product given is methanol (CH₃OH), we can deduce that the amine must be methylamine (CH₃NH₂).

**So, A = CH₃NH₂ (methylamine)**

### Step 2: Identify Compound B
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