下面是英语四级阅读单选题讲解：句子释义题。

　　For an increasing number of students at American universities, old is suddenly in. The reason is obvious： the graying of America means jobs. Coupled with the aging of the baby~boom generation, a longer life span means that the nations elderly population is bound to expand significantly over the next 50 years. By 2050,25 percent of all Americans will be older than 65，up from 14 percent in 1995. The change poses profound questions for government and society?of course. But it also creates career opportunities in medicine and health professionsand in law and business as well. In addition to the doctors，we，re going to need more sociologists，biologists，urban planners and specialized lawyers. says Professor Edward Schneider of the University of Southern Californias School of Gerontology .

　　Lawyers can specialize in elder law , which covers everything from trusts and estates to nursing-home abuse and age discrimination ? Businessmen see huge opportunities in the elder market because the baby boomers,74 million strong,are likely to be the wealthiest group of retirees in human history. Any student who combines an expert knowledge in gerontology with，say, an MBA or law degree will have a license to print money. one professor say.

　　Margarite Santos is a 21-year-old senior at USC. She began college as a biology major but found she was really bored with bacteria. So she took a class in gerontology and discovered that she liked it. She says, I did volunteer work in retirement homes and it was very satisfying.，

　　old is suddenly in most probably means ______

　　A. America has suddenly become a nation of old people

　　B. gerontology has suddenly become popular

　　C. more elderly professors are found on American campuses

　　D. American colleges have realized the need of enrolling older students

　　讲解答案：

　　B 根据第一段第二句：The reason is obvious： the graying of America means jobs.可见 学习老年学的就业优势，所以这句话的意思是老年学突然火起来。故B项是正确的。

　　下面是英语四级阅读单选题讲解：句子释义题。

　　For an increasing number of students at American universities, old is suddenly in. The reason is obvious： the graying of America means jobs. Coupled with the aging of the baby~boom generation, a longer life span means that the nations elderly population is bound to expand significantly over the next 50 years. By 2050,25 percent of all Americans will be older than 65，up from 14 percent in 1995. The change poses profound questions for government and society?of course. But it also creates career opportunities in medicine and health professionsand in law and business as well. In addition to the doctors，we，re going to need more sociologists，biologists，urban planners and specialized lawyers. says Professor Edward Schneider of the University of Southern Californias School of Gerontology .

　　Lawyers can specialize in elder law , which covers everything from trusts and estates to nursing-home abuse and age discrimination ? Businessmen see huge opportunities in the elder market because the baby boomers,74 million strong,are likely to be the wealthiest group of retirees in human history. Any student who combines an expert knowledge in gerontology with，say, an MBA or law degree will have a license to print money. one professor say.

　　Margarite Santos is a 21-year-old senior at USC. She began college as a biology major but found she was really bored with bacteria. So she took a class in gerontology and discovered that she liked it. She says, I did volunteer work in retirement homes and it was very satisfying.，

　　old is suddenly in most probably means ______

　　A. America has suddenly become a nation of old people

　　B. gerontology has suddenly become popular

　　C. more elderly professors are found on American campuses

　　D. American colleges have realized the need of enrolling older students

　　讲解答案：

　　B 根据第一段第二句：The reason is obvious： the graying of America means jobs.可见 学习老年学的就业优势，所以这句话的意思是老年学突然火起来。故B项是正确的。