A、Her friend has one. B、A salesman recommended it. C、She saw an advertisement. D、She bought one before. A

M: Hi, would you like some help?
W: Well, I’m looking for something I saw at a friend’s house a few days ago. He said he bought it here. It’s a bright metal shelf, almost a yard long, with a magnetic brace that I could attach to a cabinet or refrigerator. I’m a biologist and I want to use it for my slides and samples.
M: You are in the right department. But we don’t have it in stock now.
W: Oh, that’s too bad. Are you going to be getting more?
M: They are on order. But I should warn you the price has gone up.
W: Just my luck.
M: They were $ 12.50, but the new ones will be almost 3 dollars more. Stop in next week. We should have them by then.
W: Okay, I’ll be back.