If there aren't leaves there is no photosynthesis. Photosynthesis makes food. Leaves has clorplasts in them which make food from light and Co2
        
                    
             
        
        
        
Answer:
physical labels or identifiers
Explanation:
i think that's what you're looking for
 
        
                    
             
        
        
        
A. Bacteria are single-celled.
I think it would be this because humans have way more than one cell, and the other ones are the same as us.
Just guessing
        
                    
             
        
        
        
Answer:
A. by reacting animal fat or vegetable oil with water. 
D. by treating animal fat or vegetable oil with hydrogen
Explanation: 
Water is insoluble in animal fat or vegetable oil so it makes a layer on the surface of oil. When animal fat or vegetable oil react with hydrogen, it produces solid oil called ghee not biofuels. Biofuel is produced when animal fat or vegetable oil react with alcohol.