Historically, at the Newport Department Store, the proportion of delinquent accounts has been 14%. Newport conducted a customer communication campaign to try to reduce this percentage. After the campaign, Newport randomly selected 250 customer accounts and found that 30 were delinquent. Which of the following test statistics would be used to find the p-value to use when testing the hypothesis "the campaign had an effect" vs. "the campaign did not have an effect"?