This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
Which epidemkiological study gives the most accurate result - 
Select and explain. 
A. Meta analysis, B. Cross sectional study, C. Randomized control trail with double blinding, D. Coho study
A: Meta analysis
Answer: A: Meta analysis 
Explanation: A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Conceptually, a meta-analysis uses a statistical approach to combine the results from multiple studies in an effo to increase accuracy (over individual studies), improve estimates of the size of the effect and/or to resolve unceainty when repos disagree.