Because art is people sometimes disagree about whether something is a work of art. (select the best answer.)
a. imaginative
b. creative
c. subjective
d. skilled

Because art is (c) subjective, people sometimes disagree about whether soothing is a work of art.

All of these answers are true about art, but looking at the sentence itself subjective (which means that opinions can differ), is the only one that makes sense.