Final answer:
Plutonic or intrusive igneous rock forms from magma that cools slowly beneath the surface, resulting in coarse-grained crystals, commonly known as granite if it's predominantly light-colored.
Step-by-step explanation:
The rock that forms when a pocket of magma collects beneath Earth's surface, forming a bulge, then cools and solidifies is called plutonic or intrusive igneous rock. Specifically, when this magma cools slowly beneath the surface, it forms coarse-grained crystals. If the resulting igneous rock contains a majority of light-colored minerals and has a coarse grained texture, it is referred to as granite. Conversely, if it is primarily composed of dark-colored minerals and is fine-grained, it is called basalt, though basalt is more commonly associated with rapid cooling of lava at the surface.