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': 'Why an increased target-film distance is required in the paralleling techniques? \nSelect and explain. \nA. To avoid image magnification, B. To avoid distortion, C. To reduce scattered radiation, D. To improve film placement', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]