What best explains why there's fewer secondary consumers than producers?

because of inefficiency

Explanation:

The organisms that eat the primary consumers are meat eaters (carnivores) and are called the secondary consumers. ... Because of this inefficiency, there is only enough food for a few top level consumers, but there is lots of food for herbivores lower down on the food chain. There are fewer consumers than producers.

i believe it would cause an increase of percipitation, though i could be wrong. so i would say b is the answer.

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