After culturing the anther of a plant, a few diploid plants were found along with haploid plants. The diploid plants could have arisen from
(a) generative cell of pollen.
(b) cells of anther wall.
(c) vegetative cell of pollen.
(d) exine of pollen wall.
The diploid plants should have arisen from the cells of anther wall (option b). The generative cell, vegetative cell and exine of pollen are haploid in nature, hence any plant that would have have arisen from them will have to be haploid and can never be diploid. Thus the cells of anther wall gave rise to the diploid plants.