Final answer:
Small rocks that crystallize from magma are found in igneous rocks, which form directly from the cooling and solidification of molten material, unlike sedimentary or metamorphic rocks.
Step-by-step explanation:
Small rocks formed by magma are typically found in: c) Igneous rocks. Igneous rocks are one of the three main rock types found on Earth, which also include sedimentary and metamorphic rocks. Igneous rocks originate from the solidification of magma or lava. As magma cools, minerals begin to crystallize and interlock, forming rocks. Unlike sedimentary rocks, which are formed from the cementing of weathered rock fragments or biological debris, or metamorphic rocks, which are formed by the alteration of existing rocks due to heat and pressure, igneous rocks directly crystallize from a molten state.
Sedimentary rocks are formed from weathering processes and the cementation of broken pieces of other rocks, while metamorphic rocks are pre-existing rocks that have been altered by heat and pressure. Small rocks formed by magma are not typically found in sedimentary or metamorphic rocks, so the correct answer is c) Igneous rocks.