Final answer:
Foliation refers to the characteristic of rocks where the mineral crystals are aligned with each other, resulting in parallel planes.
Step-by-step explanation:
Foliation refers to the characteristic of rocks where the mineral crystals are aligned with each other, resulting in parallel planes. This alignment can be seen as wavy, banded lines or alternating layers of light and dark minerals. It is a texture found in metamorphic rocks that have undergone high pressure and temperature conditions.