Answer:
Igneous rocks form when magma cools and makes crystals; Igneous rocks can form both above and underground.
Metamorphic rocks form in the Earth's crust under intense pressure and heat.
Sedimentary rocks form when Igneous or Metamorphic rocks get weathered or eroded into sediments that get compacted into rocks.
The Rock Cycle:
1) magma or lava cools to form Igneous rocks
2a) the igneous rocks melt back into magma
2b) the igneous rocks turn into metamorphic rocks due to heat and pressure being applied
2c) the igneous rocks are weathered/eroded into sediment that will become sedimentary rocks through the process of compaction and cementation
3a) the metamorphic rocks are either weathered/eroded into the sediment, or melted into magma
3b) the sedimentary rocks either are weathered/eroded back into sediments, or are turned into metamorphic rocks due to heat and pressure being applied.
Explanation:
See picture