Organic reactions take place through the formations of reactive carbon intermediates formed by cleavage of covalent bonds. Formation of these intermediates depends upon the dissociation energies of covalent bonds.
In which cases, free radicals can be formed by homolytic fission ?
A. `R-overset(..)(N)=overset(..)(N)-R overset(hv)rarr`
B.
C.
D. In all cases.