🔍 BaTiO₃ – Barium Titanate

✅ BaTiO₃ is the correct answer.

BaTiO₃ is a well-known ferroelectric perovskite oxide that exhibits spontaneous polarization. The Ti⁴⁺ ion is displaced from the center of its oxygen octahedron, leading to a permanent electric dipole.

This polarization can be reversed by applying an external electric field, which is a hallmark of ferroelectric behavior. In polycrystalline (ceramic) samples, BaTiO₃ naturally forms ferroelectric domains with different polarization directions to minimize internal energy.

❌ Fe – Iron

Fe is not ferroelectric.

Iron is a metal and exhibits ferromagnetic domains, not ferroelectric ones. It does not show spontaneous polarization due to its crystal structure or electronic configuration.

✅ BiFeO₃ – Bismuth Ferrite

BiFeO₃ is multiferroic, but not the best example.

BiFeO₃ does exhibit ferroelectricity and is classified as a multiferroic material. However, its domain structure in polycrystals is more complex and not as easily observed or well-studied compared to BaTiO₃. Thus, it’s not the most straightforward example.

✅ TbMnO₃ – Terbium Manganite

TbMnO₃ shows magnetically induced ferroelectricity.

This material exhibits ferroelectricity through spin-driven mechanisms (complex magnetic ordering), usually at low temperatures. Its ferroelectric domains are subtle and harder to detect in polycrystalline form, making it a less ideal example.