Oh man i remember learning about this but i cant remember what the answer is i will see what I can do :D
        
             
        
        
        
The answer is (A) as <span> increasing risk of lung cancer is from increasing levels of exposure to outdoor air pollution and </span>particulate matter
        
             
        
        
        
Cretaceous jurassic triasic
        
             
        
        
        
I think it is the nervous system