What formed the great rift valley? a. volcanic activity and tectonic movement b. a massive earthquake 200 years ago c. a mountain range west of the valley d. a massive basin in the valley's center

Correct Answer is A. volcanic activity and tectonic movement

Explanation:

The Great Rift Valley located in central and eastern Africa is a big Geological fracture, Its formation involved the Separation of tectonic plates in a process called Divergence, which also lead to volcanic activity.

In the Divergence process, the tectonic plates are expanded by the Earth's crust, Contrary to when two tectonic plates collide and form mountains, in a divergence process the plates are being separated, creating a big ditch or trench. When the rocks sink they form a "Graben" and volcanic cones from molten lava ascending because of the tectonic movement and pressure.