I think the answer to this is 2.
r r
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Proprioception is the subconscious mechanism by which the body is able to regulate posture and movement by responding to stimuli originating in the joints, tendons, muscle, and inner ear. Proprioceptors are sensors that provide information about joint angle, muscle length, and muscle tension, which is integrated to give information about the position of the limb in space. The muscle is one type of proprioceptor that provides information about changes in muscle length. <span />
