**Core Concept**
The temporomandibular joint (TMJ) is a unique synovial joint that connects the mandible to the temporal bone. It is a complex joint that allows for both rotational and translational movements of the mandible. The TMJ is characterized by its distinct anatomy and histology, which differ from other synovial joints.

**Why the Correct Answer is Right**
The correct answer is D, as the synovial membrane in the TMJ does not cover the entire articular surface. Instead, it is limited to the peripheral areas, leaving the central part of the joint exposed. This unique anatomy allows for the exchange of nutrients and waste products between the synovial fluid and the joint cavity. The synovial membrane in the TMJ is also rich in proprioceptive receptors, which play a crucial role in the regulation of jaw movements. The absence of a complete synovial membrane covering the articular surface in the TMJ is a key feature that distinguishes it from other synovial joints.

**Why Each Wrong Option is Incorrect**
**Option A:** The TMJ is not devoid of the synovial membrane; rather, it has a unique arrangement of the synovial membrane that differs from other synovial joints.
**Option B:** The TMJ does contain synovial fluid, which is essential for the lubrication and nutrition of the joint tissues.
**Option C:** The synovial membrane in the TMJ is not rudimentary; it is a well-developed structure that plays a crucial role in the regulation of joint function.

**Clinical Pearl / High-Yield Fact**
The TMJ is a complex joint that is prone to various disorders, including TMJ syndrome, arthritis, and temporomandibular joint dislocation. Understanding the unique anatomy and histology of the TMJ is essential for the diagnosis and management of these conditions.

**✓ Correct Answer: D. The synovial membrane does not cover the articular surface.**