Meninges, Dural Folds & Venous Sinuses — Practice

A peripheral blood-free histological section of a hollow muscular viscus shows a mucosa thrown into temporary longitudinal folds (rugae), a three-layered muscularis externa with an additional innermost oblique layer, and simple columnar surface epithelium lining gastric pits. This characteristic three-layered muscularis externa identifies the organ as which of the following?