In September 2001, which of the following was used as a bioweapon agent in America?

Options

A. Botulinum
B. Anthrax (Bacillus anthracis)
C. Polio virus
D. AIDS virus

Answer

### Step-by-Step Solution:

1. **Understanding Bioweapons**:
- Bioweapons are biological agents that are intentionally used to harm or intimidate a population. They can include bacteria, viruses, or toxins.

2. **Context of the Question**:
- The question refers to a specific event in September 2001, which is significant in American history due to the terrorist attacks on September 11, 2001.

3. **Identifying the Bioweapon Used**:
- Following the September 11 attacks, there were incidents involving the mailing of letters containing anthrax spores. This event is known as the Anthrax attacks.

4. **Details about Anthrax**:
- Anthrax is caused by the bacterium *Bacillus anthracis*. It was used in the attacks that began on September 18, 2001, targeting media offices and government officials.

5. **Conclusion**:
- Based on the information, the bioweapon agent used in America in September 2001 was anthrax.

6. **Final Answer**:
- The correct answer is **Anthrax** (from *Bacillus anthracis*).