Q.55) Among the given compounds I–III, the correct order of bond dissociation energy of the C–H bond marked with ‘*’ is:
A) II $>$ III $>$ I
B) II $>$ I $>$ III
C) I $>$ II $>$ III
D) III $>$ II $>$ I
Bond Dissociation Energy is the energy needed to break a bond. Lower BDE means the resulting radical is more stable.
So the Order of Stability (and hence inverse BDE) is Benzylic > Allylic > Methyl
Hence the correct answer is (3)