When a denser oceanic plate moves underneath a less-dense continental plate, what two types of geologic structures are produced during this plate movement? a. deep-sea trench and continental arc b. deep-sea trench and island arc c. valley and hill d. hotspot and rift valley

a. deep-sea trench and continental arc

Explanation:

When an oceanic tectonic plate and continental tectonic plate meet, they create a subsuction zone. Basically, the denser oceanic plate is moving below the continental plate, moving downward toward the mantle where it gets melted. On the boundary itself, a deep-sea trench forms, which is a very deep, very steep, part of the sea which is very active geologically. Also, another trade mark feature is the formation of continental arc, which is a chain of volcanoes on the edge of the continental plate, forming because of the rising magma from the mantle layer.

answer at the divergent plate boundary in the middle of the ocean;