_________ are illegal and highly harmful chemical substances that induce a momentary feeling of happiness and change of mood.
a) Drugs
b) Sedatives
c) Tranquilizers
d) None of them

Options

A. Drugs
B. Sedatives
C. Tranquilizers
D. None of them

Answer

To solve the question, we need to identify which option describes illegal and harmful chemical substances that induce a momentary feeling of happiness and change of mood. Let's analyze each option step by step:

1. **Understanding the Question**: The question asks for a term that refers to illegal and harmful substances that can create a temporary feeling of happiness and alter mood.

2. **Analyzing the Options**:
- **a) Drugs**: Drugs are often illegal substances that can affect the brain's chemistry, particularly by increasing the secretion of dopamine, which is associated with feelings of pleasure and happiness. They can be harmful to health and are known for their potential to cause addiction.
- **b) Sedatives**: Sedatives are substances that calm the brain and reduce anxiety. They do not typically induce feelings of happiness; instead, they promote relaxation and sleepiness.
- **c) Tranquilizers**: Similar to sedatives, tranquilizers are used to reduce anxiety and promote calmness. They do not induce a euphoric feeling but rather help in managing stress and anxiety.
- **d) None of them**: This option would imply that none of the previous options fit the description, which is not the case here.

3. **Conclusion**: Based on the analysis, the option that best fits the description of illegal and harmful substances that induce a momentary feeling of happiness is **a) Drugs**.

Final Answer: **a) Drugs**

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