I think it’s A
I think so because the Synovial membrane acts as a lubricator, much like how oil lubricated the joints of the tin man. If the lubricants were removed, the friction would increase as there is no oil to decrease the friction and let the bones function properly
        
             
        
        
        
Answer:
 Start by standing with a weight in each of your hands. Your elbows should rest at your sides and your forearms should extend out in front of your body. Your knees should stay slightly bent. Bring the weights all the way up to your shoulders by bending your elbows. Once at the top, hold for a second by flexing the muscle. Reverse the motion slowly and repeat. Make sure your body is steady and you have good footing and posture. 
Explanation:
 
        
             
        
        
        
CO is produced whenever a material burns. Homes with fuel-burning appliances or attached garages are more likely to have CO problems Common sources of CO in our homes include fuel-burning appliances and devices such as: Clothes dryers. Water heaters, cars, gas stoves, generators, and power tools