Final answer:
The zone of metamorphism between country rock and intrusive igneous rock is called an aureole, where the rock undergoes changes due to heat and pressure from the intruding magma. Option number 3 is correct.
Step-by-step explanation:
The zone of metamorphism between country rock and intrusive igneous rock is known as an aureole. This term refers to the area in the surrounding country rock that has undergone metamorphic changes due to the high temperatures and pressures associated with the intrusion of magma.
As the igneous rock intrudes into the country rock, it heats the surrounding material, which can cause physical and chemical changes, leading to the formation of new metamorphic minerals and textures. These changes are dependent on the metamorphic grade, which reflects the temperature and pressure conditions during metamorphism.