Energy enters ecosystems in the form of sunlight or chemical compounds, and sunlight is the source of light in nature. Given these facts, what do ecosystems in nature need an influx of to remain feasible among the following options:
- Continuous nuclear energy.
 - Natural lipids and proteins.
 - Energy.
 - rain
 - water
 - Energy
 - oxygen
 - Renewable Sunny Delight.


 

   Energy.      