This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'If a crack occurs in epoxy composite, some microcapsules rupture near the crack and releases dicyclopentadiene which subsequently fills the crack, this type of material is known as: \nSelect and explain. \nA. Self-healing material., B. Self-assembling material., C. Smart materials., D. Bioactive materials.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: It is an automatically initiated response to damage .', 'role': 'assistant'}]