A bookstore owner wants to collect data to find out customers' opinions of the variety of book genres available at the store. Which group should she survey to get the best random sample?
A.
twenty customers who asked to share their opinions of the books available at the bookstore
B.
thirty-five randomly selected customers who purchased books at the bookstore
C.
forty-five randomly selected people at the supermarket next door
D.
fifty randomly selected customers who visited the bookstore