Select the best word or phrase that completes each sentence:…

Select the best word or phrase that completes each sentence: (addition, allylic substitution, decreases, faster, heterolysis, homolysis, increases, inductive effects, inhibitor, initiator, ionic, less, more, paired, radical resonance, selective, slower, unpaired,  with, without)   Although alkanes undergo radical substitution reactions with both Cl2 and Br2, chlorination is ……………………. than bromination.  Complete word/phrase and correct spelling (verbatim) is required. No partial credit.