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: Surgery
The proper rate of rescue breathing in an adult is: 
Select and explain. 
A. 4 times per min, B. 12 times per min, C. 20 times per min., D. 28 times per min
B: 12 times per min
Answer: B: 12 times per min 
Explanation: None