Cell membranes are made of phospholipids to keep the cell's water (cytoplasm) in and everything else out. so your answer would be D <span />
        
                    
             
        
        
        
Answer: 
All cells are made from the same major classes of organic molecules: nucleic acids, proteins, carbohydrates, and lipids.
Explanation:
 
        
                    
             
        
        
        
The answer is individual or organism 
Hope this helps
        
             
        
        
        
<span>The answers are the substances found in the
simple compounds of Hydrogen</span><span>, ammonia, methane and water and when they will undergo melting or boiling, there are weak
'intermolecular forces' that break them which is the reason why it is not a strong
covalent bond.</span>