This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: JIPMER 2017, Subject name: Radiology
[{'content': 'Hydatid sand is made of: \nSelect and explain. \nA. Scolex, B. Cyst, C. Protscolex, D. Brood capsule', 'role': 'user'}, {'content': 'Answer: C \nExplanation: * On USG, the hydatid sand looks like an echogenic material floating inside the cystic fluid. Its major component is Protoscolex.', 'role': 'assistant'}]