Which of the following is an example of chemical contamination?

Chemical contamination refers to the presence of harmful substances in food that can lead to foodborne illnesses or health issues. Pesticides are a prime example of chemical contaminants, as they are chemicals used in agriculture to control pests and diseases. When used improperly or in excess, pesticides can remain on food products, leading to consumption of harmful chemicals, which can pose serious health risks.

In contrast, fresh vegetables, cooked meat, and sealed containers do not inherently represent chemical hazards. Fresh vegetables may contain natural pesticides and nutrients, but they aren't considered chemical contamination unless they have been treated with harmful substances. Cooked meat, when properly prepared, is safe and does not involve chemical contamination unless it comes into contact with harmful chemicals. Sealed containers serve to protect food from contamination instead of being a source of it. Hence, pesticides exemplify how improper use of chemicals in food production can lead to contamination and potential health hazards.