The answer is "d. (1) values; (2) depth".
Cross-hatching provides an illusion of various "values", while impasto provides an illusion of "depth".
Cross-hatching refers to a technique which is used to make a sense of thickness or density by covering lines, and impasto is a strategy used to make a sense of depth through thickly connected paint, regularly so one can see the brush strokes. An artist may choose cross-hatching over impasto to make different qualities or degrees of gentility and darkness.And may choose impasto over cross-hatching to accentuate depth or dimension to a work of art.