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. Q.According to the passage , distance learning is basically characterized by_____
A.
A considerable flexibility in its academic requirements
B.
The great diversity of students’ academic backgrounds
C.
A minimum or total absence of face-to-face instruction
D.
The casual relationship between students and professors