Final answer:
The statement is True; pore fluids play a critical role in transporting ions during metamorphism, aiding in the recrystallization and realignment of minerals in a solid state under the effects of heat and pressure.
Step-by-step explanation:
The role of pore fluids in transporting ions in solution during metamorphism is indeed significant, making the statement True. Although metamorphism occurs in the solid state under subsolidus conditions, it requires heat to facilitate the recrystallization of minerals in the parent rock.
Elevated temperatures allow ions to migrate within the crystal structures without melting the rock. Concurrently, pressure can realign minerals, with the orientation of crystals, known as foliation, being a direct response to these conditions. In addition, chemically reactive fluids can further influence recrystallization and mineral composition. These fluids are pivotal in mediating chemical reactions and facilitating mineral changes, which is why their presence is considered instrumental in the metamorphic process.
Therefore, the statement is True. Pore fluids are crucial in the metamorphism process as they play a key role in the movement and realignment of ions within solid rocks under the influence of heat and pressure.