Question

1. which is the best example of the ultimate divergent boundary?

mid-atlantic ridge
great rift valley
red sea
east african rift

Explanation:

A divergent boundary occurs where tectonic plates move apart. The Mid-Atlantic Ridge is a major oceanic divergent boundary where the North American/Eurasian and South American/African plates separate, making it a classic example. The Great Rift Valley and East African Rift are continental rifts (early-stage divergent boundaries), while the Red Sea is a narrow sea formed by rifting but not the "ultimate" example of a fully developed divergent boundary.

Answer:

Mid-Atlantic Ridge