Dr. Brown is a history professor at a university. He has worked so hard to change negative diversity climate and disparities among cultural groups in his department

What
would be the possible top-down effect(s) that impedes Dr. Brown's efforts to make a
change?
a. Many students of color feel pressure from their peers not to be "too smart."
b. Some students explicitly demonstrate their hatred and their negative attitudes
toward certain racial/ethnic groups of students
c. Dr. Brown is required to use specific textbooks and materials in his class.
d. All of the above

c___