True. Lactic acid is caused by strenuous exercise. The lactic acid is formed because while working out, you don't receive as much oxygen.
 
        
                    
             
        
        
        
C.
Hope I helped xx
Note: Think about these issues. One is a disease, one is an addiction, and one is a virus. C is a virus because it can be multiplied and spread.
        
             
        
        
        
D.) Washed your hands first.
It is D.) because when you wash your hands first you're getting all the germs, dirt, or whatever is on your hands, off. Then you go back and put hand sanitizer to then in a sense "clean" it more. Plus who knows what is on that paper towel you just dried your hands with.