Answer: Option A.
Electrons,carbon and energy.
Explanation:
Chemorganoheterotrophs are organisms that uses organic substrates to produce carbon needed for their growth and development. They derive their energy from oxidation and reduction of organic substances. The use the reduced carbon produced by autrotophs as as source of electrons, carbon and energy. Example is fungi that uses carbon as electron donor and source for carbon and energy.
Food web provides a better model of an ecosystem and model of many different consumers
That the oxygen levels in the test tube increased and carbon dioxide levels decreased because plants produce oxygen using carbon dioxide