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
While analyzing a data, allocation into similar groups is done to ensure - 
Select and explain. 
A. Comparability, B. Accuracy, C. Validity, D. Sensitivity
A: Comparability
Answer: A: Comparability 
Explanation: Both groups (study and control) should be comparable in respect of all the possible varibles, which may influence the outcome.
So that, except for the factor under study will not influence the outcome → confoundation and bias can be minimized.