Answer: D. The fungus and bacteria organisms are obtaining the energy they need by decomposing organic matter like dead trees and old apples.
Fungi is the primary decomposer of biological waste in forest ecosystem. Fungi grows on the branching network of hyphae which provide it more penetration potential towards the litter. Wood decaying fungi has enzymes required for decomposition of lignin, a chemical substance found in wood. Fungi decompose organic matter by releasing enzymes which breaks down the decaying matter, after that they absorb the nutrients in the decaying material. The left residue in the organic matter includes sugars and amino acids are degraded and decomposed by the bacteria.
