As explained in your textbook, public speakers have an ethical obligation to avoid name$-$calling and other forms of abusive language because such language

is forbidden by the first frmendment to the U$.$S$.$ Constitution.

violates current standards of political correctness on college campuses.

changes meaning based on the frame of reference of the audience.

is used by speakers who are not fully prepared for their presentations.

demeans the personal dignity of the groups or individuals being attacked.