Answer:
One plate is being pulled under another
Step-by-step explanation:
A subduction zone is a collision between the two lithospheric plates or the two Earth's tectonic plates, one riding over the other.
At the subduction zone of the Juan de Fuca and North American Plates, one plate is being pulled under another.
Subduction zones take place where the plates collide.
The main features of subduction zones are as follows:
Ocean trenches
Volcanoes
Mountain