Answer:
C. People in different areas put their own interests ahead of the interests of the United States.
Step-by-step explanation:
Sectionalism is putting one's loyalty based on region over the entire United States. This is extremely prevalent even today, where many follow local traditions and cultures rather ahead of national interests.
For example, in the Civil War Era, the South put states right and southern cultures and the utilization of slaves over the Federal government and it's broader rules.