Which of the following is true about the joint capsule?

The joint capsule plays an important role in the stabilization of joints, which is why the choice indicating its involvement in joint stabilization is correct. The capsule is a connective tissue structure that surrounds a synovial joint, providing support and maintaining the integrity of the joint by holding the bones together.

Additionally, the joint capsule is crucial in preventing excessive movement that could lead to injuries. It is composed of two layers: the outer fibrous layer, which provides tensile strength, and the inner synovial membrane that produces synovial fluid, contributing to joint health and lubrication. This structural design not only stabilizes the joint but also allows for a controlled range of motion, ensuring that movements are performed safely and efficiently.

In contrast, the other statements do not accurately represent the primary characteristics of a joint capsule. While the joint capsule does have a rich supply of nerve endings that can respond to pain (related to option C), its main role is not primarily to allow extensive joint movement (as indicated in option D) or to be made of soft muscle tissue (reflected in option A). The focus on stabilization highlights the joint capsule's critical function in maintaining healthy joint mechanics.