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: Dental
Which of the following impact strength test measures the strength through both preswing and postswing? 
Select and explain. 
A. Charpy, B. I rod, C. Both, D. None
A: Charpy
Answer: A: Charpy 
Explanation: I Rod is newer and easier method to measure the impact strength through pre swing only.