What evolves according to natural selection?

Which direction does the energy flow in this energy pyramid ?

All annelids and arthropods have a blank body plan . unlike annelids, arthropods also have blank . the circulatory system of annelids is blank , while circulatory system of arthropods is blank .

Fill in the blank with the correct sphere label. a: ⇒ geosphere b: ⇒ biosphere c: ⇒ hydrosphere