What would happen in an ecosystem without herbivores? The populations of secondary consumers would decrease.
The populations of primary producers would decrease.
The populations of secondary consumers would increase.
The populations of primary consumers would increase.

A. The populations of secondary consumers would decrease

Explanation:

since secondary consumers obtain their energy from the herbivores which are primary consumers, therefore if there were no herbivores the secondary consumers will decrease due to inability of acquiring nutrition or food

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