Final answer:
The material most likely to be ferromagnetic based on the given magnetic susceptibility values is option c) 0.5, as ferromagnetic materials exhibit large positive susceptibilities.
Step-by-step explanation:
Based on the information provided regarding magnetic susceptibilities, a material with a magnetic susceptibility value much larger than 1 is most likely to be ferromagnetic. Ferromagnetic materials are characterized by large positive susceptibilities, as they can be magnetized to a significantly higher degree than either paramagnetic or diamagnetic materials. Paramagnetic materials have fractional susceptibilities and produce a magnetic field in alignment with the applied field, but this effect is not as strong as in ferromagnetic materials. Diamagnetic materials exhibit a negative susceptibility as they develop induced dipoles opposite to an applied magnetic field.
Given the options a) -0.02, b) 0.001, c) 0.5, and d) -0.5, the value that indicates a ferromagnetic material would be c) 0.5, as this is a positive and large number relative to the others listed. Though this number is not as large as 10³, it is significantly larger in magnitude compared to the other given options and is positive, which is a key characteristic of ferromagnetic materials.