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JEE Main levelSingle correct optionDifficulty 2 of 3g1181

Which is the correct order of stability of the following carbanions?

A $C X_{6} H X_{5} CH X_{2} X^{-} > (C X_{6} H X_{5}) X_{2} CH X^{-} > (C X_{6} H X_{5}) X_{3} C X^{-} > CH X_{3} X^{-}$
B $(C X_{6} H X_{5}) X_{3} C X^{-} > (C X_{6} H X_{5}) X_{2} CH X^{-} > C X_{6} H X_{5} CH X_{2} X^{-} > CH X_{3} X^{-}$
C $CH X_{3} X^{-} > C X_{6} H X_{5} CH X_{2} X^{-} > (C X_{6} H X_{5}) X_{2} CH X^{-} > (C X_{6} H X_{5}) X_{3} C X^{-}$
D $(C X_{6} H X_{5}) X_{3} C X^{-} > C X_{6} H X_{5} CH X_{2} X^{-} > CH X_{3} X^{-} > (C X_{6} H X_{5}) X_{2} CH X^{-}$

Answer: B

Each phenyl ring delocalises the negative charge to its ortho and para carbons (resonance, -I of sp2 carbons helps too). More phenyl groups give more delocalisation, so stability rises from methyl anion to benzyl, diphenylmethyl and triphenylmethyl anions.

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