A、$450. B、$500. C、$950. D、$1,000. C对话中，租车的费用是$500，保险的费用是$45三天，男士要租车一个月，故一共需花费$500+$450，故本题答案为C。

M: (22)I would like to rent a car with a good stereo for a whole month.
W: I think you made the right choice. Come to us. We have a wide selection of vehicles you can choose from. All our cars have stereos in them, and also air conditioning.
M: Good. (22)I am here visiting my girlfriend. I want her to have a good time.
W: Oh, is that so? Well, let me show you something she might like. It’s on our back lot.
M: This is a Porsche! But I probably can’t afford it. It must be really expensive.
W: Well, (23) it’s only $ 500 a month. You see, this car has a lot of miles on it. That’s why it’s so cheap. But it’s in nice shape, isn’t it?
M: Yes, it almost looks new.
W: Take a seat inside and see what you think.
M: OK. Wow, it’s so cool.
W: So you will take the Porsche then, sir?
M: Yes, and I want to buy the insurance too. I think it’s necessary.
W: You’re smart to buy it. (23)At 45 dollars for three days, it is a good deal.
M: Can I return the car in San Francisco?
W: San Francisco? No, sir. (24)We only have this office here. You will have to return it here.
M: Really? I heard in America you can return rental cars in different cities.
W: No, sir. That’s only with the very big companies. I’m sorry, but this car must be returned to this lot. Do you still want the car, sir?
M: Yes. It will be fun. Driving back down the coast. My girlfriend will like it.
W: It would be a beautiful drive.
M: Where are the keys?
W: (25)Just a moment, sir. We have to finish filling out the forms first.