What’s the problem being discussed in this conversation?

Listen to the conversation, mark each question as A, B, C or D according to what you hear.
W: It’s an absolute scandal. My friend Mrs Stanley says that at least twenty people have already written to the council to complain.
M: To complain about what?
W: Haven’t you heard? The gas company is thinking of pulling down all those old houses in Salt Lane and selling the land to a property company to build office blocks. And the council is doing absolutely nothing about it.
M: Well, those old houses are in pretty bad condition.
W: That’s not the point. The point is it’s not fair. There’s a housing shortage. There’re people who have been living and working in this district for over twenty years, and still haven’t got a decent place to live. It’s a shame.
M: Well, I suppose the gas company is in business like everyone else. The land those houses are built on is worth a good price.
W: Worth a good price? What we want are new homes in Salt Lane, not office blocks. One of the cashiers who works in the supermarket lives in Salt Lane. And she says she and her husband have been on the housing list since ten years ago. And every time they write, the only reply they get is a printed postcard saying"the matter is receiving attention".
M: I don’t see what it has to do with the gas company demolishing those old houses in Salt Lane. Particularly if they’re in the condition you say they are.
W: Why don’t you listen? I’ve just told you. The gas company has no right to sell that land for office blocks. It’s all wrong. The proper thing is for them to put up some high-rise flats and move those families in Salt Lane into them as quickly as possible.
M: Aren’t you getting a bit too worked up about it? I mean I’m sure the gas company knows what they’re doing.
W: Know what they’re doing! They don’t know their right hand from their left. I must say something will have to be done about it. I’m setting up a petition for a start and everyone I’ve spoken to so far has promised to sign. And there’s another thing...
M: Oh, what’s that, dear?
W: I want to write to the local paper and make a formal complaint on behalf of the residents of Salt Lane.
M: But we don’t live in Salt Lane.
W: I know but that cashier in the supermarket does. She says it’s terrible. She never knows whether she has lit her cooker properly or not, because of the smell from the gas works.
M: Uh, before you write, I’ve got something to tell you.
W: Oh, um, nothing bad, I hope.
M: No, I don’t think so. It’s just that my firm is moving offices next year.
W: Moving? Where to?
M: To one of the new office blocks in Salt Lane.