What is the benefit of testing a stroke on practice paper before filling colour?

Correct answer: Paint moisture and consistency can be checked

The governing concept is testing and controlling a painting stroke before applying it to the final work. A practice stroke shows whether the paint is too wet, too thick, too thin, or uneven, and it helps the artist adjust the water-to-paint balance and brush pressure. Therefore, option B is correct. Testing cannot enlarge the picture, make paper colour itself, or increase the number of brushes. It reduces mistakes and helps produce a more consistent final layer.