Which of the following is the most stable car | vedclass

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(D) The stability of a carbanion is increased by electron-withdrawing groups ($-I$ or $-M$ effect) and decreased by electron-donating groups ($+I$ or

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(D) The stability of a carbanion is increased by electron-withdrawing groups ($-I$ or $-M$ effect) and decreased by electron-donating groups ($+I$ or $+M$ effect).In the given options,all are substituted benzyl carbanions.$1$. $p$-methylbenzyl carbanion: The $-CH_3$ group shows $+I$ and hyperconjugation $(+H)$ effects,which destabilize the carbanion.$2$. $m$-methylbenzyl carbanion: The $-CH_3$ group shows only $+I$ effect,which destabilizes the carbanion.$3$. $p$-methoxybenzyl carbanion: The $-OCH_3$ group shows a strong $+M$ effect,which strongly destabilizes the carbanion.$4$. $m$-methoxybenzyl carbanion: The $-OCH_3$ group shows a strong $-I$ effect from the meta position (as $+M$ is not effective at the meta position),which stabilizes the carbanion.Comparing these,the $-I$ effect of the $-OCH_3$ group at the meta position makes the $m$-methoxybenzyl carbanion the most stable among the given options.

Which of the following is the most stable carbanion?

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