Answer:
B, Because they supply the examples of the main point discussed in the topic sentence
Explanation:
 
        
             
        
        
        
Coordinating conjunctions bring two clauses (subject + verb + object) together. When joining two ideas, the comma is used.
Brutus claims to be an honorable man, but he stabbed Caesar.
Contrast conjunctions introduce a contradiction with what is said before (Brutus is honorable or honest, but he is a killer).
 
        
             
        
        
        
Would be anecdotal the answer