Final answer:
Ascites is best demonstrated by sonogram of the abdomen, which uses sound waves to create images of the abdominal organs. It is a preferred method for diagnosing ascites due to its non-invasive nature and accurate detection of fluid in the abdominal cavity.
Step-by-step explanation:
Ascites is best demonstrated by sonogram of the abdomen imaging procedure. Sonogram, also known as ultrasound, is a non-invasive imaging technique that uses sound waves to create images of the organs in the abdomen. It can accurately detect the presence of fluid in the abdominal cavity, which is a characteristic feature of ascites. Other imaging procedures like CT scan and ERCP may also be helpful in certain cases, but sonogram is the preferred method for diagnosing ascites.