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

A sign of a pest infestation is indeed indicated by bite marks on food containers. This typically signifies that pests, such as rodents or insects, are accessing food supplies, which they can damage while trying to obtain food. These marks can range from small pinholes to larger bites, depending on the type of pest. The presence of bite marks suggests that the food might be contaminated, posing health risks to consumers.

While the other options may indicate various issues in a food establishment, they do not specifically point to a pest infestation. Smoky odors could imply malfunctioning kitchen equipment or poor ventilation, unusually high dust levels might suggest inadequate cleaning practices, and excessive moisture could indicate plumbing issues or poor humidity control, none of which are direct indicators of pests. Understanding the specific signs of pest infestations is crucial for maintaining food safety and hygiene in food handling environments.