In which process is black added to a colour to make it darker?

Correct answer: Making a shade

The governing concept is the distinction between tint, tone, and shade. Adding black to a colour decreases its lightness and produces a shade, so option A is correct. A tint results from adding white, while a tone is generally produced by adding grey or another neutral colour. Complementary mixing means combining hues opposite each other on the colour wheel; it is not defined by adding black. In practice, black is best introduced in very small amounts.