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: Radiology
[{'content': 'Deleterious effect of ultrasound on small organism is: \nSelect and explain. \nA. Ionisation, B. Vacoulation, C. Cavitation, D. Disintegration', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. Cavitation', 'role': 'assistant'}]