A non-biodegradable pesticide enters a food chain, and its concentration goes on increasing at each higher trophic level. What is this phenomenon called?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Biological magnification
Non-biodegradable chemicals such as DDT are not broken down or excreted, so they pile up in each organism and pass on as food. Their concentration rises at every trophic level; this is biological magnification, and the top consumers carry the highest load.