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
X-rays are produced when - 
Select and explain. 
A. Electron beam strikes the nucleus of the atom, B. Electron beam strikes the anode, C. Electron beam reacts with the electromagnetic field, D. Electron beam strikes the cathode
B: Electron beam strikes the anode
Answer: B: Electron beam strikes the anode 
Explanation: When electrons from cathode strikes the anode , X rays are produced but also there is large amount of heat production and hence tungsten having high melting point(3360c) used as a target material.