Which exercise is useful for creating different values of the same hue in acrylic colour?

Correct answer: Create tints and shades by mixing controlled amounts of white and black

The governing concept is value variation within one hue. Adding controlled amounts of white produces lighter versions, called tints, while adding controlled amounts of black produces darker versions, called shades. Arranging these mixtures from light to dark creates a useful value exercise. Therefore option C is correct. Different base colours change the hue, identical mixtures show no value range, and water mainly changes transparency rather than reliably creating a value scale.