Heroine is :

Options

A. a cannabinoid
B. commonly called 'coke' or 'crack'
C. 3, 6-diacetylmorphine (chemically)
D. used to treat mental illnesses like depression and insomnia

Answer

### Step-by-Step Solution:

1. **Identify the Substance**: The question asks about heroin. It is important to clarify what heroin is and its characteristics.

2. **Chemical Name**: Heroin is chemically known as 3,6-diacetylmorphine. This is a key point that distinguishes it from other substances.

3. **Common Names**: Heroin is often referred to by various names, including "SMAC." It is important to note that heroin is not the same as cocaine, which is commonly referred to as "coke" or "crack."

4. **Physical Characteristics**: Heroin is described as a white, odorless, and bitter crystalline substance. These characteristics help in identifying the drug.

5. **Source**: Heroin is derived from the acetylation of morphine, which is obtained from the opium poppy plant (Papaver somniferum).

6. **Methods of Use**: Heroin can be consumed in several ways, including snorting (inhaling through the nose) or injecting.

7. **Classification**: Heroin is classified as a depressant, meaning it slows down the body's functions and can affect the central nervous system.

8. **Conclusion**: Based on the information provided, the correct answer to the question "Heroin is:" is that it is chemically known as 3,6-diacetylmorphine.

### Final Answer:
Heroin is chemically known as 3,6-diacetylmorphine.

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