= Solution
{c}
A material showing <paramagnetism> has an induced <magnetization> in the direction of a weak applied field, giving positive <magnetic susceptibility>, and no spontaneous magnetization once the field is removed in the paramagnetic phase. Alignment of permanent atomic or nuclear moments is one mechanism.
A material showing <diamagnetism> develops an induced moment opposing the applied field, giving negative <magnetic susceptibility>. Closed electronic shells supply a familiar orbital contribution; the response need not require permanent moments.
A <ferromagnet> has a phase with a spontaneous ordered <magnetization> below its <Curie temperature>, produced by cooperative alignment of moments. Its <magnetic domains> can cancel in a macroscopic zero-field sample, so a measured zero net moment alone does not show that the material lacks <ferromagnetism>.
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