Which of the following statements are correct ?

A. The Amazon rainforest being cut and cleared for cultivation of soyabeans is an example of habitat loss.
B. Steller’s sea cow and passenger pigeon became extinct due to over-exploitation by humans.

C. The Nile perch introduced into Lake Victoria in East Africa helped in population growth of cichlid fish in the lake.
D. Water hyacinth is an invasive species.
E. Whenaspecies becomes extinct, the plant and animal species associated with it are not affected.

Choose the correct answer from the options given below :

**Statement A** – “The Amazon rainforest being cut and cleared for cultivation of soybeans is an example of habitat loss.”
Clearing forest removes the natural environment that many species depend on, which is precisely the definition of habitat loss. Therefore, this statement is correct.

**Statement B** – “Steller’s sea cow and passenger pigeon became extinct due to over‑exploitation by humans.”
Both species were driven to extinction by intensive hunting and exploitation: Steller’s sea cow was hunted to extinction within a few decades of its discovery, and passenger pigeons were killed in massive numbers for food and sport. Hence, this statement is correct.

**Statement C** – “The Nile perch introduced into Lake Victoria in East Africa helped in population growth of cichlid fish in the lake.”
The introduction of Nile perch had the opposite effect: it is a large predator that dramatically reduced native cichlid populations, leading to many extinctions among the cichlids. Consequently, this statement is incorrect.

**Statement D** – “Water hyacinth is an invasive species.”
Water hyacinth spreads rapidly in many freshwater systems, outcompeting native plants and disrupting ecosystems, which meets the definition of an invasive species. This statement is correct.

**Statement E** – “When a species becomes extinct, the plant and animal species associated with it are not affected.”
Extinction often triggers cascade effects, such as loss of pollinators, predators, or mutualistic partners, affecting other species. Therefore, this statement is false.

Combining the correct statements (A, B, and D) gives the answer **A, B and D only**.