单项选择题

Who are the poor in the United States As of 1970, nearly two-thirds of the poor people were white. Although nonwhites make up only one-third of those classified as poor, this reflects a great overrepresentation (过分代表) of their number because the nonwhites made up less than 16 percent of the total population in 1970.
Other categories (种类，类型) also help to define the poor. There are the aged poor. Almost one-fifth of all poor Americans are aged 65 or older. Another large segment of the poor in the United States is found in rural areas. Nearly one-fourth of all people living on farms in 1970 were classified as poor. Migrant workers and American Indians are included as part of the rural poor. But the greatest number of poor Americans is found in the cities. More than one-half of all single individuals whose income was below $3000 in 1970 lived in urban areas, as did one-half of all four-person families with incomes below $6000.
Government officials have found it important to define who the poor are because each group has different needs. Different approaches are needed to help solve the problems of the poor. According to the passage, a single individual who earns ______ in 1970 is classified as a poor person.