Which is an example of a stimulant?

Which is an example of a stimulant?

• A. Caffeine
• B. Alcohol
• C. LSD
• D. Opium

Answer: (A)

Stimulants increase brain and body activity, boosting alertness and wakefulness. Caffeine fits this by energizing you and reducing drowsiness, which is why many people use it to stay awake while driving. It works by blocking adenosine signals that make you sleepy, so you feel more awake. But the effect is temporary, and overuse can lead to jitteriness or a false sense of steadiness that can impair judgment behind the wheel. The other substances aren’t stimulants: alcohol depresses the central nervous system and slows reaction time, LSD is a hallucinogen that alters perception, and opium is an opioid that depresses brain function and breathing. So caffeine is the stimulant here.

Stimulants increase brain and body activity, boosting alertness and wakefulness. Caffeine fits this by energizing you and reducing drowsiness, which is why many people use it to stay awake while driving. It works by blocking adenosine signals that make you sleepy, so you feel more awake. But the effect is temporary, and overuse can lead to jitteriness or a false sense of steadiness that can impair judgment behind the wheel. The other substances aren’t stimulants: alcohol depresses the central nervous system and slows reaction time, LSD is a hallucinogen that alters perception, and opium is an opioid that depresses brain function and breathing. So caffeine is the stimulant here.