Answer:
D. resistance by state and local governments to the Brown v. Board of Education ruling
Step-by-step explanation:
Based on the question, the gathering of an angry mob of over 1,000 whites in Central High School as nine African Americans were escorted inside was based on the resistance by state and local governments to the Brown v. Board of Education ruling.
The Brown vs Board of Education ruling witnessed the end of racial segregation in America legally as public school segregation was deemed unconstitutional. Based on the confrontation, many whites were against this ruling and resisted by coming out to mob the black children going to the previously all white schools and they had to be protected by Federal Marshals.