The correct option is A Peduncle
The seed is endospermic in Ricinus. A characteristic of castor seed is the presenee of caruncle which develops from peduncle. The fruit is a spiny, greenish capsule containing large, oval, shiny, bean-like, highly poisonous seeds with variable brownish mottling.
A capsule is a type of simple, dry fruit produced by many species of flowering plants. A capsule is a structure composed of two or more carpels. Castor seeds have a warty appendage called as the caruncle, which is a type of elaiosome. The seeds are endospermic or albuminous where the embryo is embedded in the endosperm and nucellus, which the seedling will use upon germination.
Therefore, the correct answer is option A.