1. The process shown in the diagram is Subduction process.
- The Subduction process is a geological process where the oceanic lithosphere is been recycled into the Earth's mantle at the convergent boundaries.
- The process is caused when tectonic plates slides underneath another one.
2. The Letter A in the diagram indicates a Deep-Ocean trench.
- The deep ocean trenches are usually long.
3. The oldest area in the diagram is B. because the plate has been in long existence and slides underneath another plates.
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