The correct option is B A carbanion (−−CH2)
Hyperconjugation :
It is a stabilising effect due to the reason that octet of carbon is always complete. Stability is also increased due to the delocalisation of sigma-pi electrons.
Condition for hyperconjugation :
Atleast one α hydrogen has to be present.
Hyperconjugation is mainly observed in:
1. A free radical (−∙CH2)
2. A carbocation (−+CH2)
3. A double bond >C=C<
It is not observed in carbanion because of its fully filled p-orbital (or octet).