Answer: Earthquakes and Volcanic eruptions
Explanation:
You did not attach a picture however, this should be the correct answer.
Mid-oceanic ridge plate boundaries such as the Mid-Atlantic Ridge form as a result of plate separating at the boundary. This leads to earthquakes due to the forces of tension acting on the plates.
When this happens, the mantle is exposed and therefore there will be volcanic eruptions as the lava comes to the surface as magma. When this magma cools it creates new seafloors and underwater mountains.
