Joints come in two types: _________.

• A. Movable
• B. Immovable
• C. Elastic and rigid
• D. Movable and Immovable

Answer: (D)

Joints are classified by how much they allow bone movement. Immovable joints (like the sutures between skull bones) don’t permit movement, while movable joints (such as the knee or elbow) allow a range of motions. Although some joints are only slightly movable in some contexts, the common two-type classification used here is movable and immovable. Options describing elastic and rigid refer to material properties rather than movement, so they don’t fit.