What causes several visible bands at equal intervals in a gradation?

Correct answer: Drying between stages and sudden tonal changes

The governing concept of smooth gradation is a continuous change in tone while the adjoining paint remains workable. If each stage dries before the next is joined, or if the tone changes abruptly, separate bands remain visible instead of merging. Option A is correct. A clean brush generally improves control, and paper direction or the colour’s name cannot create repeated tonal bands. A maintained wet edge helps prevent them.