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
The amount of X-rays which undergo Compton scattering are: 
Select and explain. 
A. 7%, B. 23%, C. 57%, D. 70%
C: 57%
Answer: C: 57% 
Explanation: Compton scattering occurs when a photon interacts with an outer orbital electron. About 57% of interactions in a dental X-ray beam exposure involve Compton scattering.