Answer:
Sea mount.
Step-by-step explanation:
Underwater mountain is also known as Sea mount. Mauna Kea is the tallest mountain that is present in underwater having the height of 10,200 meters (33,500 feet) when measured from the base. Underwater mountain is located where tectonic plates are spreading apart. when the lava came out, it spreads on the ocean floor and with the passage of time, it becomes taller and in the end mountain is formed.