Nicotine ​

A) ​is a depressant for smokers, but a stimulant for nonsmokers.
B) ​is the primary reason that people begin smoking.
C) ​is more important than social pressure for starting to smoke.
D) ​is known to have properties making it addictive.

Nicotine

A toxic, addictive substance found in tobacco plants that stimulates the release of dopamine in the brain, contributing to its addictive properties.

Depressant

A substance that reduces the functioning of the nervous system, often used to decrease anxiety and induce sleep.

Stimulant

A substance that raises levels of physiological or nervous activity in the body, often used to increase alertness or physical performance.