Which one of the following carbanions is the least stable ?

Options

A. `CH_(3)CH_(2)^(-)`
B. `HC-=C^(-)`
C. `(C_(6)H_(5))_(3)C^(-)`
D. `(CH_(3))_(3)C^(-)`

Explanation

An organic ion with a pair of availabe electrons and a negative charge on the central carbon atom is called a carbanion .
Electron attracting group `(-CN,gtC=O)` increases stability and electron releasing group `(-CH_(3)` etc) decreases the stability of carbanion ,
In `(CH_(3))_(3)C^(-)`, three `-CH_(3)` groups (electron releasing group) are present present , so it is least stable .