Question

which statement best describes the illustration? a volcano forms at an oceanic - oceanic convergence boundary. a mountain forms at a divergent boundary. a rift valley forms at continental - continental convergence boundary. a trench forms at a transform boundary.

Explanation:

• Analyze each option:
• Option A: At oceanic - oceanic convergence boundaries, one oceanic plate subducts under another. Magma rises from the subduction zone, leading to volcanic formation (like island arcs with volcanoes). The illustration shows a volcano, and this process matches.
• Option B: Mountains at divergent boundaries are rare; divergent boundaries (like mid - ocean ridges) form new crust, not typical mountain - building (mountains at convergent boundaries, especially continental - continental). So this is incorrect.
• Option C: Continental - continental convergence forms mountains (like the Himalayas), not rift valleys (rift valleys form at divergent boundaries in continents). So this is incorrect.
• Option D: Trenches form at oceanic - oceanic or oceanic - continental convergence boundaries, not transform boundaries (transform boundaries have fault - related activity, like earthquakes, not trench formation). So this is incorrect.

Answer:

A. A volcano forms at an oceanic - oceanic convergence boundary.