Respuesta :
A change which would remove the source of this error is to: Test a fourth group, in which participants do not receive the mineral supplements.
What is a scientific method?
A scientific method can be defined as the various techniques that are adopted to observe, investigate, examine and study a particular thing while giving explanations on the basis of the evidence, theory, proof, hypothesis, or factual information they derived from the research work.
In this scenario, a claim was made by the company its mineral supplements can effectively prevent common cold. However, this claim was disputed by a scientist because there exist an error in the group setup.
How to remove an error in science
For this investigation, an effective and efficient way to remove this source of error would be by testing a fourth group, in which the mineral supplements is not administered to any of the participants.
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