The stability of carbanions in the following (I) RC C Θ (II) (III) R C CH Θ (IV) R C CH Θ is in the order of (AIPMT 2008)

Carbanions are those chemical species which bears the negative charge on carbon and also possesses eight electrons in its valence shell. The stability of these carbanions depends on the percentage of s-character. Higher the s-character, higher will be stability. The 50% s-character gives it the most stability. The phenyl carbanion comes next to it. It is more stable than the other two because of the delocalization of the negative charge by the resonance effect. Thus it will come second after (I). Thus, the correct option is (a) (I) > (II) > (III) > (IV)