At a convergent boundary:
B. A subduction zone forms.
Explanation:
1. Convergent boundaries are where two tectonic plates move towards each other.
2. When one plate is denser than the other, it subducts or goes under the less dense plate.
3. This subduction process often results in the formation of a deep trench and volcanic activity.
4. The subducted plate can melt and create magma that rises to the surface, forming volcanoes.
5. The collision of plates at convergent boundaries can lead to intense geological events like earthquakes and mountain building.
Therefore, at a convergent boundary, a subduction zone forms as one plate moves beneath another.
