A large grocery store chain believes that 73% of its customers use the store's "Savings Card" when they make purchases. The manager in charge of the "Savings Card" program has randomly sampled 24 customers and observed whether or not they used the card. Complete parts a through c. . . .. . a. Assuming that the 73% use rate is correct, what is the probability that 18 or more people in the sample used the card? The probability is (Round to four decimal places as needed.) b. Repeat the calculation in part a assuming that the use rate is 63%; that it is 78%. If the use rate is 63%, the probability is (Round to four decimal places as needed.) If the use rate is 78%, the probability is (Round to four decimal places as needed.) c. Based on your calculations, if 18 people in the sample used the card, which of the three use rates do you think is most accurate? Explain. Choose the correct answer below. O A. The 73% use rate is the most accurate because it is the closest to the expected value. O B. The 78% use rate is the most accurate because it is the furthest from the expected value. O C. The 63% use rate is the most accurate because it is the closest to the expected value. O D. The 78% use rate is the most accurate because it is the closest to the expected value