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
What is the function of filtration process while taking radiographs? 
Select and explain. 
A. Remove the short wavelength photons, B. Remove the portion of long wavelength photons, C. To increase the radiation dose to patient, D. To increase scatter of secondary radiation
B: Remove the portion of long wavelength photons
Answer: B: Remove the portion of long wavelength photons 
Explanation: None