Which record is most useful for accurately reproducing an acrylic mixture?

Correct answer: A record of colour, water or medium ratios with a dry sample

The governing concept is reproducibility: an acrylic mixture can be recreated only when its ingredients and proportions are recorded. Writing the colour names, the water or medium ratio, and keeping a dry sample provides both a recipe and a visual check after drying. Option A is therefore correct. A colour name, brush number, or painting size alone cannot specify the mixture accurately.