In muscular anatomy, the origin of a muscle is typically attached to the portion of the bone that remains stationary during movement.

• A. Immovable
• B. Movable
• C. Center
• D. Rotating

Answer: (A)

The origin is the anchor point that stays stationary when the muscle contracts. When a muscle shortens, it pulls on its insertion toward this fixed point, producing movement at the joint. That’s why immovable is the best choice: it describes the bone portion that remains relatively fixed during the action, serving as the stable reference the muscle pulls against. The other terms don’t describe this anchor relationship—the end that moves toward the origin is the insertion, and terms like movable, center, or rotating don’t capture that stationary-attachment concept.