What is a characteristic feature of a ganglion cyst?

A ganglion cyst is characterized by being a mass that contains a jelly-like viscous fluid, which is typically a thick, gelatinous substance often composed of a mixture of hyaluronic acid and other viscous components. These cysts generally arise from the synovial tissue of joints or tendon sheaths and can vary in size. The fluid-filled nature of ganglion cysts can lead to a smooth, round appearance that differentiates them from other types of masses.

Other potential options, such as a solid mass of bone, an infected bursa, or a benign lymph node enlargement, do not accurately describe the composition or characteristics of a ganglion cyst. A solid mass of bone would indicate a bony tumor or growth, while an infected bursa would involve inflammation and possibly acute pain, which is not typical of a ganglion cyst. Benign lymph node enlargement pertains to the lymphatic system and is not related to the fluid-filled nature of ganglion cysts. Thus, the defining feature of a ganglion cyst is indeed the presence of the jelly-like viscous fluid it contains.