Carbohydrates and lipids are both sources of energy. The breaking of carbon and hydrogen bonds on carbohydrates and lipids release energy for use by the cells.
        
             
        
        
        
Is chemistry for reactions to take place energy must be provided. As heat is a form of energy, the more the heat, the more the energy, the faster the reaction occurs
        
                    
             
        
        
        
Connective tissues
Connective tissues are made up of fibrous cells. Blood and Bone are good examples of specialized connective tissues.
        
             
        
        
        
Rough ER - protein synthesis, transport of proteins throughout the cell
Smooth ER - lipid synthesis and cell detoxification
        
             
        
        
        
The answer is: A. collecting data
During this process , researchers would use their observational skills and record every notable occurrence that happen to the variables. 
The focus on this process is simply to add all relevant data without making any analyzation. That process come later on after the researchers started to change the variables in order to see whether it would create a correlation.