Here's why:

* Extrusive refers to the process of magma (molten rock) erupting onto the Earth's surface.

* Intrusive igneous rocks, on the other hand, are formed when magma cools and solidifies beneath the Earth's surface.

Examples of extrusive igneous rocks include:

* Basalt

* Rhyolite

* Andesite

* Obsidian

* Scoria