Which term describes a substance that alters body function?

Which term describes a substance that alters body function?

• A. Bioassay
• B. Assay
• C. Drug
• D. Black Box Warning

Answer: (C)

A substance that alters body function is a drug. In pharmacology, a drug is any chemical that, once inside the body, changes how a body part or system works. This broad idea covers medicines, stimulants, depressants, toxins, and more because each can modulate physiological processes. The other terms describe things related to testing or labeling—bioassay is a test measuring a substance’s biological effect, an assay is a general test for activity, and a black box warning is a safety alert about risks, not a substance itself. So the best fit for "a substance that alters body function" is drug.

A substance that alters body function is a drug. In pharmacology, a drug is any chemical that, once inside the body, changes how a body part or system works. This broad idea covers medicines, stimulants, depressants, toxins, and more because each can modulate physiological processes. The other terms describe things related to testing or labeling—bioassay is a test measuring a substance’s biological effect, an assay is a general test for activity, and a black box warning is a safety alert about risks, not a substance itself. So the best fit for "a substance that alters body function" is drug.