Which movement describes anterior displacement of a body part without angular movement?

• A. Inversion
• B. Retraction
• C. Protraction
• D. Eversion

Answer: (C)

Protraction is forward movement of a body part along the plane of the body without changing its angle. This describes anterior displacement by sliding the part forward rather than bending or rotating it. An example is protruding the jaw forward or moving the shoulder blade forward when reaching ahead. In contrast, retraction moves a part backward toward the midline, and inversion/eversion are movements of the foot that involve turning the sole in or out with angular rotation. So the described motion fits protraction perfectly.