The correct option is A Coconut
Seed coat is not thin in coconut. The fruit is an indehiscent fruit in which an outer fleshy part-exocarp or skin and mesocarp or flesh surrounds a shell of hardened endocarp with a seed inside. These fruits usually develop from a single carpel and mostly from flowers with superior ovaries. The definitive characteristic of a drupe is that the hard, lignified stone is derived from the ovary wall of the flower. The coconut is a drupe, but the mesocarp is fibrous or dry, so this type of fruit is classified as a simple dry fruit, fibrous drupe.
Therefore, the correct answer is option A.