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': 'Crimp marks on the radiograph are due to: \nSelect and explain. \nA. Droplets of fixing solution, B. Droplets of developer, C. Excess application of pressure, D. None of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]