Answer:
Are you.
Explanation:
none of the answers above make sense
 
        
                    
             
        
        
        
Answer:
B.
Explanation:
A and C have awkward sentence structure because "when a car needs many serious repairs, it might be cheaper to buy a new car", it repeats the word car again making it redundant and in C, "When a car had needed many serious repairs, it might be cheaper to buy a new one", it has wrong use of past-tense. 
 
        
             
        
        
        
Personification , as they ‘ fly ‘