Which of the following is an example of a biological contaminant?

Biological contaminants are primarily organisms such as bacteria, viruses, fungi, and parasites that can pose a risk to food safety and public health. The correct answer, which refers to bacteria in food, exemplifies a biological contaminant because bacteria are living microorganisms that can grow in food, potentially leading to foodborne illnesses. Food safety practices require strict attention to the presence of these microorganisms to prevent contamination, spoilage, and health risks associated with consuming unsafe food.

In contrast, cleaning chemicals are classified as chemical contaminants, while pest droppings fall under physical contaminants associated with pests. Hair and nails, although potentially hazardous in terms of physical contamination, do not fall under the biological category because they are not living organisms. Understanding the different types of contaminants helps in implementing proper food safety protocols.