A researcher conducted a survey and found that people who took vitamin C every day had fewer colds than people who did not take vitamin C every day. The researcher wrote a paper stating that vitamin C prevents colds, using this data as evidence. What is wrong with this conclusion?
The study relied on the observations of the consumers.
The study did not take into account other health-related factors.
The survey was administered to the general public.
The survey is not a reliable data collection method.
1 answer
Maybe people who take vitamin C do not go out in the rain without an umbrella. So B.
2 answers