A bank wants to get new customers for their credit card. They try two different approaches in their marketing campaign. The first promises a "cash back" reward, and the second promises low interest rates. A sample of 500 people is mailed the first brochure; of these, 125 get the credit card. A separate sample of 500 people is mailed the second brochure; 150 get the credit card. Are the two campaigns equally attractive to customers? Find the test statistic.
a. z = -1.89
b. z = 2.80
c. z = 0.25