(A) Areolae
(B) Rugae
(C) Villi
(D) Typhlosole
Answer - (B) Rugae
Explanation: The stomach is the expanded part of the digestive tract into which the esophagus opens. The empty stomach has a number of folds or ridges, called rugae, formed by the submucosa and mucosa, which serve to accomodate the filling and expanding of the stomach. Rugae are more prominent in the lower, narrow region of the stomach. The mixing and partial digestion of food by the stomach’s gastric secrtions produces a pulpy fluid mix called chyme.