Question

Select all that apply.

The "twelve-tone" technique _____.

ensures that the 12 notes are given equal importance
ensures that the music will be on key
is characterized by the works of Arnold Schoenberg
is part of Expressionism music

Answer 1

Your two best options are:
ensures that the 12 notes are given equal important.
and:
is characterized by the works of Arnold Schoenberg.
the twelve-tone technique was made by Arnold Schoenberg and is also called "serialism" and "dodecaphony." It's a method that rejects keys.