Answer:
The correct answer will be -Bursae
Step-by-step explanation:
A bursa is a thin, fluid-filled connective tissue sac present around the synovial joints where it helps reduces the fiction caused by the rubbing of the bones, ligaments and tendons. The bursae are classified on the basis of their presence in the human body.
The Bursae reduce the friction by between two structures of the skeletal system by physically separating the adjacent structures due to the presence of the fluid.
Thus, Bursae is the correct answer.