Statement I is correct because alkyl groups exert a +I effect (electron-donating inductive effect). This increases the electron density on the negatively charged carbon atom, destabilizing the carbanion. Thus, as the number of alkyl groups increases, the stability of the carbanion decreases. The order of stability is CH3−>CH3CH2−>(CH3)2CH−>(CH3)3C−.
Statement II is incorrect because allyl and benzyl carbanions are highly stabilized by the resonance effect, where the negative charge is delocalized over the adjacent π bonds or the benzene ring, rather than by the inductive effect.
Answer: Statement I is correct but Statement II is incorrect