Researchers want to determine which cold remedy is most effective at controlling cold symptoms. They are considering three

Question

Researchers want to determine which cold remedy is most effective at controlling cold symptoms. They are considering three methods of gathering data: 
Method A: Researchers give cold remedy A or cold remedy B to people with colds and then observe the duration of the cold symptoms exhibited by each group. 
Method B: Researchers observe the cold symptoms exhibited by people with colds who choose to take cold remedy A and people with colds who choose to take cold remedy B. 
Method C: Researchers ask people with colds if they feel better after taking cold remedy A or cold remedy B. 
Tell whether each method of gathering data is a survey, an observational study, or an experiment. Which option would give the most reliable results?

Kunduz · Accepted Answer

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