Answer: Option 2: Stubby was a stray that had proved himself in battle. 
Explanation: It makes the most sence based on the short story. Also they asked why they took him on the battlefield, not why the kept him in general.
 
        
                    
             
        
        
        
Lol what ?? what is this asking ?
        
                    
             
        
        
        
Answer:
.............. I would but where I live its midnight already sorry!!
 
        
             
        
        
        
Answer:
Demon slayer and I won't Reply to your quote sorry- 
Explanation: