Which exercise is most useful for creating different oranges in a sunset?

Correct answer: Make a sample strip of red-yellow ratios

The governing concept is controlled colour mixing. Orange is produced by combining red and yellow, and changing their proportions shifts the mixture toward a redder or yellower orange. A sample strip records these ratios and makes comparison and selection easier, so option A is correct. Applying one orange removes variation; repeated blue addition changes the hue toward a duller neutral; black and white alter value, not orange hue.