Diagram A and B are both examples of [blank_start]divergent[blank_end] plate boundaries.
Diagram A is an example of two [blank_start]oceanic[blank_end] plates moving apart. Diagram B is an example of two [blank_start]continental[blank_end] plates moving apart.
At the plate boundary on diagram A, land is being [blank_start]created[blank_end] by magma coming up and cooling. The magma comes up to create a long series of volcanoes called a [blank_start]ridge[blank_end]. [blank_start]Earthquakes[blank_end], in addition to volcanoes, also occur at this plate boundary.
At the plate boundary on diagram B, the thick continental crust is stretching and a [blank_start]rift valley[blank_end] is being made. Over time, the rift valley will get wider and deeper. [blank_start]Earthquakes[blank_end] also occur at this plate boundary.
Digram C is a [blank_start]transform[blank_end] boundary. Land is [blank_start]not created[blank_end] or destroyed at this plate boundary. Strong [blank_start]earthquakes[blank_end] occur at this plate boundary, and a [blank_start]fault[blank_end] is formed where the crust cracks between the two plates.