It will form extrusive igneous rock. Beyond that they exact type will vary.
Extrusive igneous rocks
Type your answer here... were do you go when a volcano erupts
is the type of volcano that often erupts with a mix of stream,ash,rock and dust causing a pyroclastic folw
When lava cools on the surface, it forms igneous rock called basalt.
That depends on the chemistry of magma the volcano erupts - Basalt, andesite, rhyolite etc. but Generically the rock coming out of a volcano is called lava rock (pahoehoe or aa) but one can also get pumice or ignimbrites.
is the type of volcano that often erupts with a mix of stream,ash,rock and dust causing a pyroclastic folw
All three rock types could be formed in areas under the seas. Two types of rock are most likely to form on the seafloor, however. Sedimentary rock is formed on the seafloor where accumulations of sediments undergo lithification processes. Extrusive igneous rock can form on the seafloor when lava erupts on its surface.
extrusive igneous rock
lava
volcanoes create igneous rocks
rock
Volcanoes form when magma (molten rock) rises to the surface, creating openings in the Earth's crust. This magma eventually erupts onto the surface as lava, building up and forming a volcano over time. The type of volcano that forms depends on the type of magma it contains and how it erupts.