The correct option is D Seed coat
Cotton is a soft, fluffy staple fiber that grows in a boll or protective capsule, around the seeds of cotton plants of the genus Gossypium in the family of Malvaceae. The fiber is almost pure cellulose. Under natural conditions, the cotton bolls will tend to increase the dispersion of the seeds. Cotton is a seed hair fiber produced from epidermal seed coat. Cotton fibers are not obtained from root hairs, stem hairs or leaf.
Therefore, the correct answer is option D.