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By almost any measure , there is a boom in Internet-based instruction . In just a few years , 34 percent of American universities have begun offering some form of distance learning (DL), and among the larger schools , it’s closer to 90 percent . If you doubt the popularity of the trend, you probably haven’t. It enrolls 90,000 student, a statistic used to support its claim to be the largest private university in the country.
While the kinds of instruction offered in these programs will differ, DL usually signifies a course in which the instructions post syllabi(课程大纲), reading assignments , and schedules on Websites , and students send in their assignments by e-mail . Generally speaking, face-to-face communication with an instructor is minimized or eliminated altogether.
What accounts for the high drop-out rates for online students？
A) There is no strict control over the academic standards of the courses.
B) The evaluation system used by online universities is inherently weak.
C) There is no mechanism to ensure that they make the required effort.
D) Lack of classroom interaction reduces the effectiveness of instruction.
