Question

which statement describes what is happening at the plate boundary in this section of a tectonic map?
the seafloor is spreading.
an oceanic plate is subducting.
two continental plates are colliding.
two plates are sliding past each other.

Explanation:

The map likely shows a convergent boundary where an oceanic plate (denser) subducts beneath another plate (e.g., along the west coast of South America, the Nazca Plate subducts under the South American Plate). Seafloor spreading is at divergent boundaries (mid - ocean ridges), continental - continental collision forms mountains (like Himalayas), and sliding past is transform (like San Andreas). So the correct process here is subduction of an oceanic plate.

Answer:

B. An oceanic plate is subducting.