The correct option is B Gizzard
Gizzard is an organ found in the digestive tract of some animals like birds, earthworms, some fishes and some crustaceans. This specialized stomach is constructed of thick muscular walls and it is used for grinding up food, often aided by particles of stone or grit. It is bird's second chamber. Gizzard is disc-shaped in birds, very muscular and in many birds, it contains small stones that facilitate grinding of foodstuffs.