How do bones attach to other bones across joints?

Bones attach to other bones across joints primarily by means of ligaments. Ligaments are strong bands of connective tissue that provide stability to joints by connecting bones to each other. They help support the joint structure and limit excessive movement, thus preventing injury.

While cartilage does play a role in joints by providing a cushioning surface between bones and allowing for smooth movement, it is not the structure that directly connects bones to one another. Muscles are responsible for moving bones at joints but do not connect bones together. Tendons connect muscles to bones rather than bones to bones.

The key role of ligaments in maintaining the integrity and stability of joints is what makes this choice the most accurate in regards to how bones connect across joints.