Congress Grass is

Options

A. Cynodon dactylon
B. Digitaria purpurea
C. Cymbopogon citratus
D. Parthenium hysterophorus.

Answer

**Step-by-Step Solution:**

1. **Identify the Common Name**: The question asks for the common name of Congress Grass.

2. **Review the Options**: The options provided are Syndon, Dictalon, Digitaria perfurea, Symbogon citratus, and Parathenium hysteropterus.

3. **Research the Options**:
- Check which of the options is commonly known as Congress Grass.
- Parathenium hysterophorus is known for its invasive nature and is often referred to as Congress Grass.

4. **Understand the Plant Family**:
- Parathenium hysterophorus belongs to the Asteraceae family, which is also known as the Aster family.

5. **Historical Context**:
- Note that this species was introduced in India as an alien species and later became invasive, affecting indigenous species.

6. **Conclusion**:
- Based on the research and understanding, the answer to the question "Congress Grass is" is **Parathenium hysterophorus**.

**Final Answer**: Congress Grass is **Parathenium hysterophorus**.

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