If the Pacific Ocean is shrinking (seafloor is disappearing) and the Atlantic Ocean is expanding (seafloor is being formed), the types of plate boundaries that must be involved in each location are A. Pacific Ocean, convergent; Atlantic Ocean, divergent. At convergent boundaries, denser land suducts beneath lighter land. In an ocean's case, the seafloor is always more dense than the continent it is colliding with. This means that the seafloor subducts beneath the continent and slowly travels back to the mantle. At divergent boundaries, volcanoes lining deep-sea trenches constantly erupt which forms land that moves onto each side of the trench thereby creating new seafloor.
The correct answer is D. British.
Just trinna get some points
