听力原文： In the United States, the average age of a college student used to be between eighteen and twenty-six years old. Not any more. Over the years, this has changed. Now many colleges and universities boast a large number of non-traditional students.
Many of these non-traditional students are older than the traditional students. Senior citizens are joining the ranks of non-traditional students on campuses throughout the United States. These non- traditional students frequently work during the day and go to school at night or on weekends. They may have started college after they graduated from high school, but later, because of family, or work responsibilities, had their education interrupted.
Traditional Students benefit from having older students in their classes. Senior citizens are excellent role models for some younger students who may not take college as seriously as they should. Senior attend college or the university, not because they have to, but because they want to. Some senior citizens take individual college courses only for personal enrichment. Others attend college to fulfill their lifelong dream of earning college degrees.
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A. Under the ages of eighteen.
Between the ages of eighteen and twenty-six.
C. Between the ages of twenty-six and fifty-six.
D. Over sixty-five years of age.