Which description accurately distinguishes a 'residue' from a 'contaminant' in food-safety terminology?

• A. A residue is a chemical deliberately applied (e.g., pesticides) that should be at low regulated levels at consumption, whereas a contaminant is an unwanted hazardous substance (e.g., heavy metals, dioxins) that ideally should not be present.
• B. Residues and contaminants are synonymous terms in regulatory language and there is no distinction in how agencies like EPA, FDA, or USDA manage them.
• C. Residues are always harmless because they are regulated, while contaminants are always harmful and always present at high levels in foods produced in industrialized nations.
• D. A residue refers only to microbial remnants after processing, while contaminants are exclusively chemical substances, so residues cannot include pesticides or industrial chemicals.

Answer: (A)