Where does energy first come into an ecosystem? A producers make energy
B the sunlight provides energy to producers
C consumers obtain energy from animals
D scavengers obtain energy from dead plants

B. Sunlight provides energy to producers

Explanation: photoautotrophs (plants) produce energy from sunlight by photosynthesis. This is the only energy production based on an external source of energy. Plants, whether alive or dead, are consumed by heterotrophs - bacteria, fungi and animals. The nutrients and energy from dead heterotrophs (and some live ones) are recycled by both autotrophs and heterotrophs.