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Question
Which of the following limits the number of trophic levels in a food chain?
(a) insufficient food supply from producer level
(b) decrease in energy at higher trophic levels
(c) increase in the number of organisms at higher trophic levels
(d) accumulation of harmful chemicals at higher trophic levels
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Solution
Decrease in energy at higher trophic levels
According to the 10 per cent law, the amount of energy decreases in each trophic level, and hence the number of trophic levels in a food chain is limited.
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