This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fundamentals in Radiology, Subject name: Radiology
What is the difference between X-rays and Gamma rays? 
Select and explain. 
A. X-rays are produced extranuclearly whereas gamma rays are produced in nuclear decays, B. X-rays have higher energies than gamma rays, C. Gamma rays are produced by bremsstrahlung, D. X-rays and gamma rays interact with matter differently
A: X-rays are produced extranuclearly whereas gamma rays are produced in nuclear decays
Answer: A: X-rays are produced extranuclearly whereas gamma rays are produced in nuclear decays 
Explanation: X rays are produced when accelerated electrons strike heavy metal nucleus and are deflected with deceleration. Gamma rays are produced intranuclearly to stabilize nucleus of the radioactive element.Reference: Khan Physics of Radiation therapy; 5th edition