A. It is a relatively frequent finding at diagnostic imaging. B. It is a well-known hallmark feature of acute cholecystitis. C. The finding itself is non-specific and can be found in a wide range of gallbladder diseases and extracholecystic pathological conditions. D. Sonography is not sufficient as the initial imaging technique for evaluating patients with suspected gallbladder disease, because of its moderate sensitivity in the detection of gallbladder dimensions.