Which of the following statemetns is false?

Options

A. psychoactive drugs alter activity of nervous system
B. hallucinogen can alter one's thoughts, feelings and perceptions
C. mescaline is a stimulant
D. depression is a mood disorder characterised by hoplessness, sadness, decline in interest, energy, concentration and changes in sleep pattern and appetite.

Answer

To determine which statement is false among the given options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Analyze Option 1**: "Psychoactive drugs alter activity of the nervous system."
- **Explanation**: This statement is true. Psychoactive drugs are known to affect the brain's function, altering mood, perception, and behavior by interacting with neurotransmitters in the nervous system.

2. **Analyze Option 2**: "Hallucinogens can alter one's feelings and perceptions."
- **Explanation**: This statement is also true. Hallucinogens, such as LSD and psilocybin, can significantly change a person's sensory perceptions and emotional state, leading to altered experiences of reality.

3. **Analyze Option 3**: "Mescaline is a stimulant."
- **Explanation**: This statement is false. Mescaline is not a stimulant; it is classified as a hallucinogen. It is derived from the peyote cactus and is known for causing hallucinations, similar to LSD.

4. **Analyze Option 4**: "Depression is a mood disorder characterized by hopelessness, sadness, loss of interest, low energy, concentration difficulties, and changes in sleep patterns and appetite."
- **Explanation**: This statement is true. Depression is indeed characterized by these symptoms, which affect a person's daily functioning and overall well-being.

### Conclusion:
Based on the analysis, the false statement is **Option 3**: "Mescaline is a stimulant."

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