The answer is Complement 
this is for my Gradpoint fellas 
 
        
                    
             
        
        
        
Answer:
These crops where improved  with technology, production of high-yielding variety, and improve farm practices. All these ensured  the crops of green revolution had increase yield. 
Explanation:
Through  genetic engineering, high-yielding variety of cereals e.g wheat, maize, rice, were genetically engineered so that certain features which enhanced increased productivity were selected for.
Use of fertilization, the adoption of mechanization,good cropping and farming system are other factors which enhanced yield of these crops. Specifically, these crops were modified to enhance their Nitrogen uptake, which promotes rapid growths.
 
        
             
        
        
        
Answer:
im pretty sure its A. ATP was a thing talked about a lot on this topic
Explanation:
 
        
             
        
        
        
The first three answers are natural changes, while the last three are because of human intervention.