For most terrestrial ecosystems, pyramids composed of species abundances, biomass, and energy are similar in that they have a broad base and a narrow top. the primary reason for this pattern is that
a. secondary consumers and top carnivores require less energy than producers
b. at each step, energy is lost from the system
c. biomagnification of toxic materials limits the secondary consumers and top carnivores
d. top carnivores and secondary consumers have a more general diet than primary producers

The correct option is b.  at each step, energy is lost from the system

Explanation:

The amount of energy that travels from one trophic level to another is known to declines at each level. Infact, only 10% of the energy travels from one trophic level to another.

This is because most of the energy is lost by the organisms at each trophic level. It is due to the metabolic processes which occur in the organisms of each trophic level  and most of the energy is lost as heat.

a symbiotic relationship with the mitochondria