Answer 1: The correct answer is b. convergent continental-continental boundary.
A convergent continental-continental boundary refers to a convergent plate boundary where two continental plates meet or come together. When this happens, a forceful collision occurs, and structures like mountains start to form. The Himalaya mountain range is formed as a result of the convergence of the Indian and Eurasian continental plates.
Answer 2: The correct answer is d. convergent oceanic-oceanic boundary.
Volcanic island arcs refers to a curved line of volcanoes formed from the subduction (sinking) of one oceanic plate below another plate. Examples of volcanic island arcs include Japanese Islands and Alaskan Islands.
Answer 3: The correct answer is b.convergent oceanic-continental boundary.
A continental volcanic arc is an arc-shaped chain of volcanoes that form from the subduction of an oceanic plate under a continental plate.