AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.
(B) Biological magnification
The progressive accumulation of non-degradable chemicals at each successive trophic level in a food chain is called biological magnification.
The key phrase is "progressive accumulation at each successive trophic level." Biological magnification (biomagnification) is the correct term — concentrations of harmful chemicals like pesticides increase as we move up the food chain. Eutrophication refers to excess nutrients in water bodies; biodegradation and decomposition are breakdown processes, not accumulation. This concept is directly covered in Chapter 13 (Our Environment).