Which type of contamination is caused by improper food handling that leads to the presence of harmful microorganisms?

The correct choice is the type of contamination caused by the presence of harmful microorganisms, which falls under biological contamination. This includes bacteria, viruses, parasites, and other pathogens that can cause foodborne illnesses. These harmful microorganisms can thrive in food when it is not handled properly, such as when it is kept at unsafe temperatures, comes into contact with contaminated surfaces, or is prepared using unsanitary practices.

In the context of food safety, understanding biological contamination is critical because it directly relates to public health. The risks associated with biological contaminants are significant, as they can lead to outbreaks of foodborne illnesses, affecting large numbers of people if not properly controlled through safe food handling practices.

Other types of contamination do not pertain to microorganisms. Physical contamination involves foreign objects being inadvertently introduced into food, such as pieces of glass or metal. Chemical contamination refers to the presence of harmful substances through cleaning agents or pesticides that can contaminate food. Allergenic contamination involves specific allergens triggering reactions in susceptible individuals, which is a different aspect of food safety. Therefore, biological contamination is the key area of concern specifically linked to harmful microorganisms.