Answer is: (CH3)C.
Carbon has four bonds in organic compound.
1) in (CH3)CH, carbon has four single bonds, one with hydrogen and three witn methyl group (CH₃), so he is not radical.
2) in (CH3)C, carbon has three single bonds and one free electron.
3) in (CH3)C+, carbon has three single bonds and no free electrons, he is carbocation, not radical.
