Though it is mere 1 to 3 percent of the population, the upper class possesses at least 25 percent of the nation’s wealth. This class has two segments: upper-upper and lower-upper. Basically, the upper-upper class is the "old rich"—families that have been wealthy for several generations—an aristocracy of birth and wealth. Their names are in the Social Register, a listing of acceptable members of high society. A few are known across the nation, such as the Rockefellers, Roosevelts, and Vanderbilts. Most are not visible to the general public. They live in grand seclusion, drawing their income from the investment of their inherited wealth. In contrast, the lower-upper class is the "new rich". Although they may be wealthier than some of the old rich; the new rich have hustled to make their money like everybody else beneath their class. Thus their prestige is generally lower than that of the old rich, who have not found it necessary to lift a finger to make their money, and who tend to look down upon the new rich.
However its wealth is acquired, the upper class is very, very rich. They have enough money and leisure time to cultivate an interest in the arts and to collect rare books, painting, and sculpture. They generally live in exclusive areas, belong to exclusive social clubs, communicate with each other, and marry their own kind—all of which keeps them so distant from the masses that they have been called the out-of-sight class. More than any other class, they tend to be conscious of being members of a class. They also command an enormous amount of power and influence here and a broad, as they hold many top government positions, run the Council on Foreigh Relations, and control multinational corporations. The actions affect the lives of millions.
The upper class is also called the out-of-sight class because（）
A. they keep away from the general public
B. they spend most of their time abroad
C. they don’t communicate with any people
D. they move frequently from place to place