The term ‘biomagnification’ refers to the 

• Biomagnification is an accumulation of toxic substances in the body of living organisms at a higher level than the present in the non-living environment.
• Organic magnification or amplification is also called as biomagnification.
• An increase in the concentration of non - degradable pollutants as they pass through the food chain is referred to as biomagnification.

Hence, option D is the correct answer.