Biodiversity and Conservation — NEET UG practice

1. This question requires checking each statement against the known causes of biodiversity loss (habitat loss, over-exploitation, alien species invasion, and co-extinction).

2. Statement A: Clearing the Amazon rainforest for soyabean cultivation removes the natural habitat of countless species — this is a textbook example of habitat loss, so A is correct.

3. Statement B: Steller's sea cow and the passenger pigeon are well-known examples of species driven to extinction because humans hunted them excessively — this is over-exploitation, so B is correct.

4. Statement C: In reality, the Nile perch introduced into Lake Victoria caused the extinction of over 200 species of cichlid fish rather than helping them, so C is incorrect.

5. Statement D: Water hyacinth is indeed a well-documented invasive alien species that chokes water bodies, so D is correct.

6. Statement E: When a species goes extinct, other species that depend on it (in a mutualistic or obligatory relationship) often go extinct too — this is called co-extinction — so E is incorrect as written.

Since A, B, and D are the true statements:

Hence, the answer is Option B.

1. This question checks the difference between in situ and ex situ conservation.

2. In situ conservation means protecting species within their own natural habitat, without removing them from where they naturally live.

3. Sacred groves are patches of forest that local communities protect because of religious or cultural beliefs — since the organisms remain in their natural surroundings, this qualifies as in situ conservation.

4. Why the other options are wrong: Wildlife safari parks, botanical gardens, and seed banks all involve keeping organisms or their parts (seeds, specimens) outside their natural habitat under artificial management — these are examples of ex situ conservation, not in situ.

Hence, the answer is Option A.

1. This question tests recall of the term "Evil Quartet", which is the name given to the four major causes of biodiversity loss.

2. The four recognised causes are:

• Habitat loss and fragmentation
• Over-exploitation
• Alien species invasions
• Co-extinctions

3. Why the other options are wrong: Options mentioning air pollution, water pollution, or soil pollution replace one of the true four causes with a pollution-based factor, which is not part of the standard "Evil Quartet" list.

Since Option C lists exactly the four correct causes:

Hence, the answer is Option C.