This answer is
not correct. The initial reaction in this mechanism
will be the reaction of an alkoxy radical with HBr producing an alcohol and
bromine radical. Hydrogen radicals are very unstable and would not be formed in
this first step. The bromine radical then reacts with propene. The intermediate
radical formed after this addition must also be the more stable of the 2 that
are possible. Think about these factors and try another selection.