01 What is a likely cause if dark edges form on watercolour paper?
Answer and explanation
Correct answer: D. Excess water and pigment collected at the edges of the wash
Explanation: The governing concept is the drying behaviour of a watercolour wash. If a bead of water carrying pigment remains at the edge, evaporation draws the pigment toward that boundary. After drying, the accumulated pigment forms a darker line, often called a hard or backrun edge. Option D is correct. Very white paper does not cause the effect, and dilution alone is not the decisive problem unless excess liquid is left at the boundary.