Marijuana, hashish, charas and ganja are produced by group of chemical known as :-

Answer

**Step-by-Step Solution:**

1. **Identify the substances in question**: The question mentions marijuana, hashish, charas, and ganja. These are all substances derived from the cannabis plant.

2. **Understand the chemical group**: These substances are produced by a specific group of chemicals. The key to answering the question lies in identifying this group.

3. **Define the chemical group**: The group of chemicals that includes marijuana, hashish, charas, and ganja is known as cannabinoids.

4. **Source of cannabinoids**: Cannabinoids are primarily obtained from the plant Cannabis sativa. This plant is the source of various cannabinoids that can be either natural or synthetic.

5. **Examples of cannabinoids**: Some well-known examples of cannabinoids include THC (tetrahydrocannabinol) and CBD (cannabidiol), which are found in the cannabis plant and are responsible for the psychoactive and medicinal effects associated with these substances.

6. **Medical uses and implications**: Cannabinoids have been used for medical purposes, such as pain relief, anxiety reduction, and inducing sleep. However, their abuse can lead to negative effects, including hallucinations and social issues.

7. **Conclusion**: Therefore, the answer to the question is that marijuana, hashish, charas, and ganja are produced by a group of chemicals known as cannabinoids.

**Final Answer**: Cannabinoids.

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