The addictive drug found in tobacco leaves is called:

• A. Nicotine
• B. Stimulant
• C. Leukoplakia
• D. Tar

Answer: (A)

Recognizing the addictive drug found in tobacco. Nicotine is the specific chemical responsible for tobacco dependence. It is an alkaloid that is absorbed when tobacco is smoked or chewed and acts on nicotinic acetylcholine receptors in the brain, triggering dopamine release in reward pathways. This creates the reinforcing effects that lead to craving, tolerance, and withdrawal, making nicotine the key driver of addiction to tobacco. Tar, on the other hand, is a mixture of many chemicals that contributes to cancer risk rather than to addiction, and leukoplakia is a mouth lesion associated with tobacco use, not a drug. While nicotine does act like a stimulant, the precise term for the addictive substance is nicotine itself.