At which boundary is subduction more likely to occur?

• A. Transform plate boundary
• B. Destructive plate boundary
• C. Conservative plate boundary
• D. Constructive plate boundary

Answer: (B)

Subduction happens when two plates collide and one is forced to sink into the mantle, which only occurs at convergent boundaries. These are called destructive boundaries because crust is removed as the subducting plate dives beneath the overriding plate. At transform boundaries the plates slide past each other horizontally, with earthquakes but no sinking; at constructive boundaries the crust is created as plates move apart, not subducted. Conservative is another term sometimes used for transform boundaries, which also doesn’t involve subduction. So subduction is most likely at the destructive (convergent) boundary.