In my opinion the least offensive types of music are classical on its own and trance, simply because they doesn't contain any words and therefore the potential for offense is pretty much zero.
Why do some people kill another person/other people???
Why do some people murder other people??? Everyone has a right to life! Since , in my opinion, a person should not be killed unless they're killed by soldiers who have both wide-spread International support , & coƱrmed , orders, to do so!