A department store manager wants to know if a greater proportion of customers on the store\textquotesingle s mailing list would redeem a coupon for $\textbackslash$$5 off the price of an item than would redeem a coupon for 10 percent off the price of anitem. The manager mails a $\textbackslash$$5 off coupon to a random sample of 500 customers and mails a 10 percent off coupon to an independent random sample of 500 customers. The number of coupons of each type that were redeemed was recorded. Assuming that the conditions for inference are met, what test procedure should be usedto answer the manager\textquotesingle s question? 
选项为:A:A one-sample t-test for a mean  B:A one-sample z-test for a proportion  C:A t-test for the slope of a regression line  D:A matched-pairs t-test for a mean difference  E:A two-sample z-test for a difference between two proportions  请回答其中一个选项.