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New oceanic crust is created at rift zones. Where is the old crust destroyed?
AAt mid-ocean ridges
BAt mountain ranges
CAt subduction zones
DAt volcanic hot spots
Answer & Solution
Correct answer: C. At subduction zones
1. Earth is not growing, so crust made in one place must be lost in another.
2. At a subduction zone one plate is forced down beneath another into the mantle.
3. The plate melts at depth and its material rejoins the mantle flow.
4. Mid-ocean ridges are rift zones, so they make new crust rather than destroy it.
_Source: OpenStax Astronomy (CC BY 4.0), section 8.2 Earth’s Crust_
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