In which technique do lines cross one another to create darker values?

Correct answer: Cross-hatching

Correct answer: D, cross-hatching. Hatching uses a group of generally parallel lines for shading. Cross-hatching adds another group of lines that crosses the first group, often at an angle. The overlapping lines place more marks in the same area, so that area can look darker and can show changes in form or shadow. Option A is wrong because ordinary hatching normally consists of one principal direction of parallel lines; it does not specifically require crossing sets. Option B is wrong because stippling uses dots, not crossing lines. Option C is wrong because a wash uses a fluid layer of diluted colour or pigment to create an even or gradual tone, rather than a network of crossing lines. Option D is correct because the name itself describes lines crossing each other. The darkness can be controlled by line spacing, pressure, direction, and the number of layers. Memory cue: one direction is hatching; crossing directions are cross-hatching.