Which of the following is a common sign of a pest infestation?

Visible droppings or nests are indeed a common sign of a pest infestation. This is because many pests, such as rodents and certain insects, leave behind droppings as they move through an area in search of food and shelter. These droppings can vary in size, shape, and color depending on the type of pest present. Additionally, nests can indicate the presence of pests, as they often build nests or burrows in hidden areas to establish their colonies or shelters.

Identifying these signs is crucial for pest control technicians, as they can help in accurately diagnosing the type of pest involved and determining the most effective course of action for elimination and prevention. Recognizing visible droppings or nests enables a technician to evaluate the extent of the infestation and take necessary measures to address it promptly.