The fruit of the coconut is a large, dry drupe composed of a thin outer layer (exocarp), a thick, fibrous middle layer called as a mesocarp and a hard inner layer called as an endocarp that surrounds a large seed. A small, cylindrical embryo is embedded in the endosperm nutritive tissue just opposite the functional germination pore. The seed is surrounded by an outer brown layer called as the seed coat or testa. Thus, the correct answer is option D.