An energy-rich organic compound needed by organisms is ?

The energy-rich compound needed by organism is : Carbohydrates
Carbohydrates consist of the combination of the existing Carbon, Hydrogen, and Oxygen alone.
For human, The source of carbohydrates could be found in almost every food, but the huge amount could be found in rice, potato, corn, cassava, oatmeal, etc

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Number one is sinkholes may form from water erosion