Considering the answers;
a. De jure segregation still exists.
b. De facto segregation still exists.
c. There is very little segregation in the U.S. today.
d. Segregation is more vital today than in the past.
Answer;
B. De facto segregation still exists.
Explanation;
De facto segregation is a racial segregation, especially in public schools, that happens, by fact, rather than by legal requirement. For example, often the concentration of African-Americans in certain neighborhoods produces neighborhood schools that are predominantly black, or segregated in fact, and not by law.