C. Channel proteins bind to molecules too large to diffuse into or out of the cell, and allow them to pass.
        
             
        
        
        
Answer:
1. Stratus
2. Cirrus
3. Cumulus
4. Both Cumulus and Cirrus
Explanation:
 
        
                    
             
        
        
        
The answer to this question would be: vertebrae 
In vertebrae fracture, traction is important to assure immobilization of the vertebrae. Movement can cause the fragment of bone in the fracture damaging the neural tissue in the vertebrae.
To ensure no movement in the neck, metal tongs can be put on the skull. The tongs will help fixate the skull with the shoulder.