01 Which sample is most useful as a control in a colour-mixing experiment?
Answer and explanation
Correct answer: A. An unchanged sample of the base colour
Explanation: The governing concept is comparison with a control or reference sample. An unchanged sample of the original colour provides a fixed baseline, so the observer can judge exactly how hue, value or saturation changed after mixing. Thus option A is correct. The darkest or muddiest sample is only an experimental result, and an unlabelled sample cannot support reliable comparison or identification.