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
Which epidemiological study gives the most accurate result - 
Select and explain. 
A. Meta analysis, B. Cross-sectional study, C. Randomized control trial with double blinding, D. Cohort study
A: Meta analysis
Answer: A: Meta analysis 
Explanation: None