The congres grass/carrot grass that causes allergy arrived in India in 1956. It is

Options

A. Parthenium hysterophorous
B. Eichhornia crassipes
C. Opuntia dilleni
D. Sorghum halepens

Answer

**Step-by-Step Solution:**

1. **Identify the Plant**: The question mentions "congress grass" or "carrot grass," which is known to cause allergies.

2. **Historical Context**: It is noted that this plant arrived in India in 1956. This gives us a timeframe for understanding its introduction and impact.

3. **Classification**: The congress grass is classified as an "alien species." This means it is not native to the region where it is found, which in this case is India.

4. **Scientific Name**: The scientific name of congress grass is *Parthenium hysterophorus*. This is an important detail as it helps in the identification of the species in scientific contexts.

5. **Impact on Agriculture**: The plant acts as a weed and decreases the yield of other crops. It competes for nutrients in the soil, which can hinder the growth of native crops.

6. **Conclusion**: Based on the information provided, the congress grass is indeed an alien species that causes allergies and negatively impacts agriculture.

**Final Answer**: The congress grass, scientifically known as *Parthenium hysterophorus*, is an alien species that arrived in India in 1956 and causes allergies.

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