**Core Concept:** Innervation of joints is essential for joint movement, sensation, and protection by reflex arc. Innervation is provided by sensory neurons, which convey information about joint position, force, and movement to the central nervous system, and motor neurons, which control muscle contraction for joint movement and protection.

**Why the Correct Answer is Right:** Innervation of joints is provided by the peripheral nervous system, specifically the somatic and autonomic nervous systems. Innervation of joints by the autonomic nervous system is incorrect as it primarily controls involuntary actions, while joints require conscious control for movement and protection. Sensory neurons from the somatic nervous system, however, innervate the skin surrounding the joint, muscles, and tendons, providing sensation, protection, and movement control.

**Why Each Wrong Option is Incorrect:**

A. **Skeletal muscles:** Skeletal muscles are involved in joint movement and stabilization but are not innervated by the autonomic nervous system. They are under somatic control.

B. **Autonomic ganglia:** Autonomic ganglia are involved in controlling involuntary functions and do not innervate joints.

C. **Autonomic nerves:** Autonomic nerves are responsible for controlling involuntary functions and are not involved in joint innervation.

D. **Autonomic receptors:** Autonomic receptors are involved in detecting changes in internal organs, blood vessels, and glands, not joint innervation.

**Clinical Pearl:** Understanding the correct innervation of joints is crucial in diagnosing and treating neuropathic joint pain conditions such as reflex sympathetic dystrophy (RSD) and complex regional pain syndrome (CRPS). These conditions manifest with joint pain, swelling, and limited range of motion despite normal joint structure, requiring a thorough knowledge of joint innervation for proper diagnosis and management.