The correct answer is: **B - Ascites** **Explanation:** - **Ascites** is the accumulation of fluid in the peritoneal cavity, leading to increased abdominal girth. - When percussing the abdomen of a patient with ascites, **tympany** (a drum-like sound) is typically heard **at the top of the abdomen** (over the bowel that floats on top of the fluid), while **dullness** is heard over the fluid that settles to the dependent (lower) parts of the abdomen. - This pattern (tympany on top, dullness on the flanks) is characteristic of ascites. **Other options:** - **A - Gas:** Gas throughout the abdomen would cause generalized tympany, not just at the top. - **C - Tumor:** A tumor would usually produce localized dullness, not tympany. - **D - Obesity:** Fat does not produce tympany; it may make percussion sounds less reliable and more muffled. **Summary:** Tympany at the top of the abdomen with increased girth is a classic finding in **ascites**.