Which factor might increase the likelihood of pest infestation in homes?

High moisture levels in a home create an environment conducive to pest infestations. Pests, particularly termites, cockroaches, and various types of fungus, thrive in damp conditions. Moisture can come from several sources, such as leaks in plumbing, inadequate drainage, or high humidity levels, all of which attract pests seeking water and suitable nesting sites. When moisture accumulates, it not only provides the necessary hydration that many pests need to survive but can also compromise the structural integrity of the house, making it more vulnerable to infestations. Therefore, managing moisture levels is essential for preventing pest problems in residential settings.

The other factors presented would generally contribute to pest control and prevention rather than increasing the likelihood of infestations. For example, using organic building materials, while potentially less toxic, doesn't attract pests. Regular cleaning and maintenance effectively reduce pest hideouts and food sources, while non-toxic repellents are designed to deter pests rather than invite them in.