A、People who restore old houses. B、People who sell houses. C、People who design new houses. D、People who want to buy a house. A这是

In today’s class we’ll be examining some nineteenth-century pattern books that were used for building houses. I think it’s fair to say that these pattern books were the most important influence on the design of North American houses during the nineteenth century.
    This was because most people who wanted to build a house couldn’t afford to hire an architect. Instead, they bought a pattern book, picked out a plan, and took it to the builder. The difference in cost was substantial. In 1870, for example, hiring an architect would’ve cost about a hundred dollars. At the same time, a pattern book written by an architect cost only five dollars.
    At that price, it’s easy to see why pattern books were so popular. Some are back in print again today, and of course they cost a lot more than they did a hundred years ago. But they’re an invaluable resource for historians, and also for people who restore old houses. I have a modern reprint here that I’ll be passing around the room in a moment so that everyone can have a look.
1. What was in pattern books?
2. What course would this talk be most appropriate for?
3. According to the speaker, why were pattern books so popular?
4. According to the speaker, who uses pattern books today?