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: Social & Preventive Medicine
Random is Randomization Implies 
Select and explain. 
A. Unequal and known chances, B. Equal and known chances, C. Unequal and unknown chances, D. Equal and unknown chances
B: Equal and known chances
Answer: B: Equal and known chances 
Explanation: None