Which of the following is not a visual element of art

Based on the text preview as well as research about the background of the novel in and the authors life, a reader can predict the novel will mostly be about. the novel is: setting background for watsons a. a young boy who marches in washington as part of the civil right movement b. family who is persecuted by oppoents of the civil right movement c. group of persons who decide to take a trip south to join the civil rights movement d. a group of siblings who learn about the effect of the civil right movement on their family. i really sure it's d but correct me if i'm wrong