xy13中一个逻辑问题求助

shuoben

community activist: if M  wants to keep its central shopping distric healthy,it should prevent the opeening og a huge S discount department store on the outskirts of M ,Records from other small towns show that whenever S ahs openned a store outside the central shopping distrcit of a small town ,within5 years the town has experienced the bankcrupticies of more than a quater of the stores in the shopping district

To answer to which of the following would be most useful for evaluating the community activist's reasoning?

(B) Do a large percentage of the residents of M currently do almost all of their shopping at stores in ,?

(C )in towns with healthy central shopping districts,what proportion of the stores in those districts suffer bankcruptcy during a typcial 5-year period .