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Predict the major product 'P' in the following sequence of reactions:
A
(2-methylcyclopentyl)methanamine 
B
(1-methylcyclopentyl)methanamine 
C
1-cyano-2-methylcyclopentane 
D
1-cyano-1-methylcyclopentane 
Explanation
Peroxide effect adds Br at C-2 (anti-Markovnikov). Nucleophilic substitution with KCN yields 2-methylcyclopentanecarbonitrile. Reduction by Na(Hg)/EtOH (Mendius reduction) yields (2-methylcyclopentyl)methanamine.
Detailed Solution
Reaction step 1: Free radical anti-Markovnikov addition of HBr in the presence of benzoyl peroxide to 1-methylcyclopentene gives 1-bromo-2-methylcyclopentane (Br attaches to the less substituted carbon). Reaction step 2: Cyanide substitution ($S_N2$) with KCN replaces Br by CN, yielding 2-methylcyclopentanecarbonitrile. Reaction step 3: Reduction of nitrile group with $\text{Na(Hg)}/\text{C}_2\text{H}_5\text{OH}$ (Mendius reaction) reduces $-\text{CN}$ to $-\text{CH}_2\text{NH}_2$, producing (2-methylcyclopentyl)methanamine.