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
Ideal position for dentist to stand while taking radiographs 
Select and explain. 
A. Behind head of patient, B. At an angle of 90-135 degrees and six feet away from patient, C. In 11'o clock position, D. At an angle of 180° and 9 feet away
B: At an angle of 90-135 degrees and six feet away from patient
Answer: B: At an angle of 90-135 degrees and six feet away from patient 
Explanation: None