Formation of the bony callus in fracture repair is followed by:

Choice A reason: Tendons connect muscles to bones and transmit force during contraction. They do not act as cushions or reduce friction.

Choice B reason: Bursae are the correct answer. These are small fluid-filled sacs lined with synovial membrane that reduce friction between moving structures such as tendons and bones or skin and bones. They are commonly found near joints like the shoulder, elbow, and knee.

Choice C reason: Menisci are fibrocartilaginous pads found in certain joints like the knee. They help distribute weight and improve joint stability but are not fluid-filled sacs.

Choice D reason: Joint cavities are spaces within synovial joints that contain synovial fluid. While they allow movement, they are not separate cushioning structures like bursae.

Choice E reason: Ligaments connect bones to other bones and stabilize joints. They do not serve as cushions or reduce friction.

Choice A reason: The sella turcica is correctly named, but it is located on the sphenoid bone, not the ethmoid. This makes the pairing incorrect.

Choice B reason: The crista galli is a projection of the ethmoid bone and serves as an attachment point for the falx cerebri, not for protecting the pituitary gland. Additionally, it is not located on the sphenoid bone.

Choice C reason: This is the correct answer. The sella turcica is a saddle-shaped depression in the sphenoid bone that houses and protects the pituitary gland. It is a central feature of the cranial floor.

Choice D reason: The occipital condyles are located on the occipital bone and articulate with the first cervical vertebra. They have no role in protecting the pituitary gland.

Choice E reason: While the crista galli is correctly paired with the ethmoid bone, it does not protect the pituitary gland. Its function is related to the attachment of meninges.