What type of fabric is most preferred by fabric pests?

Fabric pests, such as moths and carpet beetles, are particularly attracted to soiled fabrics, especially those that have been stained with human sweat or oils, as these substances provide additional nutrients beneficial for their growth and development. Fabrics that are clean and free of organic residues are less likely to attract pests, as they find little to sustain them.

Woolens are also highly susceptible to damage from pests since the natural fibers are a preferred source of protein for larvae. However, the primary factor that makes soiled fabric with human sweat the most attractive is the presence of organic materials that pests feed on. While leather and cotton may have their susceptibility, they do not generally offer the same level of attraction without the presence of oils or dirt. Therefore, soiled fabric with human sweat represents the ideal target for these pests, making it the correct answer to this question.