In MOOCs (Massive Open Online Courses), an initiative under the NME-ICT programme, the fourth quadrant is related to

In the MOOCs four-quadrant design the fourth quadrant is self-assessment.

It lets learners test their own understanding through quizzes and exercises.

E-content forms the reading-material quadrant, not the fourth.

E-tutorial is the video-lecture quadrant that comes first.

Web resources make up the supplementary reference quadrant.

The four quadrants together structure a complete online course.