Which cue will help most to show glass and water differently?

Correct answer: Different behaviour of transparency reflection and edge

The correct answer is C: use differences in transparency, reflections, and edge behaviour. Glass and water can both be transparent, so simply naming a colour or leaving white paper is not enough to identify them. Observe what each material does to light. Glass often shows a firm contour, bright reflected highlights, and visible changes caused by its plane or thickness. Water may show a surface line, reflected light, transparency, and distortions or patterns beneath the surface; the exact appearance depends on the situation. The artist should compare the object with its surroundings rather than apply a random blue tone. Option A is insufficient because colour names do not describe surface behaviour. Option B can suggest light but cannot distinguish materials alone. Option D concerns presentation, not material qualities. Memory cue: material is shown by its response to light, not by colour alone.