Why is a control experiment included in an investigation?
Answer and explanation
Correct answer: C. To show the result is due to the factor tested
- Step 1: A control has all conditions the same except the factor.
- Step 2: Any difference is therefore due to the factor being tested.
Answer
To show the result is due to the factor tested.
Why not the others: To make the investigation last longer overall: duration is not the purpose. To increase the number of variables in the test: controls reduce variables. To remove the need for repeats of the test: repeats are still needed.
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