Linked from
The 7 pages that link to Intrusive rock, each with the reason it gives.
GraniteNarrower topic: Granite’s underground origin is the defining feature of an intrusive rock.
GabbroNarrower topic: Gabbro is an intrusive rock, cooled slowly underground.
DioriteNarrower topic: Diorite is intrusive; underground cooling allows its crystals to grow coarse.
GranodioriteNarrower topic: Granodiorite’s crystals grow as its magma cools underground.
BatholithNarrower topic: A batholith is a large exposed body of intrusive igneous rock.