Three solid samples are tested with a strong bar magnet.
• Sample X is strongly attracted and retains noticeable magnetization after the magnet is removed.
• Sample Y is weakly attracted and shows no residual magnetization once the magnet is taken away.
• Sample Z is weakly repelled by the magnet.
Identify the magnetic classification (ferromagnetic, paramagnetic, or diamagnetic) of each sample and briefly state the observation that supports each choice.