Adolescence is the period of dramatic physical and psychological changes in a person. An adolescent person is at high risk of falling in the trap of drug or alcohol abuse.
Nicotine acts as a stimulant because it mimics the effect of:

Explanation

**Step-by-Step Solution:**

1. **Understanding Adolescence**: Adolescence is a critical developmental stage characterized by significant physical and psychological changes. During this time, individuals are particularly vulnerable to substance abuse, including drugs and alcohol.

2. **Identifying Nicotine**: Nicotine is a psychoactive substance commonly found in tobacco products, as well as in smaller amounts in tea and coffee. It is known for its stimulant properties.

3. **Mechanism of Action**: Nicotine acts as a stimulant in the body. To understand how it does this, we need to look at its interaction with neurotransmitters.

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