Two elderly neighbors have lived next door to one another for 25 years. They provide daily care, share important decisions, celebrate holidays together, and publicly describe each other as family. Why might a sociologist classify this relationship as a family?

• A. The relationship involves long-term residence within the same community
• B. The relationship fulfills family functions despite lacking biological or legal ties
• C. The relationship demonstrates the importance of neighborhood solidarity
• D. The relationship reflects a household based on shared economic resources