The passage mainly discusses ______.A．the improved

单项选择题

Passage 2 Questions 6 to 10 are based on the following passage. Seventeenth-century houses in colonial North America were simple structures that were primarily functional, carrying over traditional designs that went back to the Middle Ages. During the first half of the eighteenth century, however, houses began to show a new elegance. As wealth increased, more and more colonists built fine houses. Since architecture was not yet a specialized profession in the colonies, the design of buildings was left to carpenters who undertook to interpret architectural manuals imported from England. There are an astonishing number of these handbooks for builders in colonial libraries, and the houses erected during the eighteenth century show their influence. Most domestic architecture of the first three-quarters of the eighteenth century displayed a wide range of taste and freedom of application of the rules laid down in these books. Increasing wealth throughout the colonies resulted in houses of improved design, whether the material was wood, stone or brick. New England still favored wood, though brick houses became common in Boston and other towns, where the danger of fire forced people to use more durable material. A few houses in New England were built of stone, but only in Pennsylvania and its neighboring areas was stone widely used in dwellings. An increased use of bricks is noticeable in Virginia and Maryland, but wood remained the most popular material even in houses built by wealthy landowners. In the Carolinas, even in the crowded town of Charleston, wooden houses were much more common than brick houses. Eighteenth-century houses showed great interior improvements over their predecessors. Windows were made larger and shutters removed. Large, clear panes replaced the gray glass of the seventeenth century. Doorways were larger and more decorative. Fireplaces became decorative features of rooms. Walls were sometimes elaborately decorated. White paint began to take the place of blue, yellow, green and gray colors, which had been popular for walls in the earlier years. After about 1730, advertisements for wallpaper styles in scenic patterns began to appear in colonial newspapers.

The passage mainly discusses ______.

A．the improved design of the 18th century colonial houses
B．the role of carpenters in building the 18th century houses
C．the varieties of decorations used in the 18th century houses
D．a comparison of the 18th century houses and modern houses