In the following which plant is also called 'Terror of Bengal'?

The correct answer is Option (2) → Eichhornia

Option (1) Parthenium — Incorrect. Parthenium (carrot grass) is an invasive land weed whose pollen causes allergies.

Option (2) Eichhornia — Correct. Water hyacinth grows abundantly in nutrient-rich water and chokes water bodies.

Option (3) Lantana — Incorrect. Lantana is an invasive land weed of forests.

Option (4) Vallisneria — Incorrect. Vallisneria is a submerged water plant known for pollination by water; it is not a pest.

Note: This question is from Chapter 16, Environmental Issues, of the pre-rationalised NCERT book. This chapter is not in the present NCERT book (2026-27). The extract below is from the pre-rationalised edition.

NCERT Extract (Pre-rationalised edition, Chapter 16, Environmental Issues):
Domestic Sewage and Industrial Effluents – “… You may have seen the beautiful mauve-colored flowers found on very appealingly-shaped floating plants in water bodies. These plants which were introduced into India for their lovely flowers have caused havoc by their excessive growth by causing blocks in our waterways. They grow faster than our ability to remove them. These are plants of water hyacinth (Eichhornia crassipes), the world’s most problematic aquatic weed, also called ‘Terror of Bengal’.”