A marketing researcher wants to estimate the mean amount spent ($) on a certain retail website by members of the website's premium program. A random sample of 97 members of the website's premium program who recently made a purchase on the website yielded a mean of $1500 and a standard deviation of $250. Complete parts (a) and (b) below. a. Construct a 90% confidence interval estimate for the mean spending for all shoppers who are members of the website's premium program. Sus (Round to two decimal places as needed.) b. Interpret the interval constructed in (a). Choose the correct answer below. O A. There is a 90% probability that mean spending in dollars for all shoppers who are members of the website's premium program is between the lower and upper limits of the confidence interval. O B. The sample mean spending in 90% of all samples of 97 members of the website's premium program will be between the lower and upper limits of the confidence interval. O C. 90% of all shoppers who are members of the website's premium program have spent an amount in dollars that is between the lower and upper limits of the confidence interval. O D. With 90% confidence, the mean spending in dollars for all shoppers who are members of the website's premium program is between the lower and upper limits of the confidence interval