Which are the biotic components of the forest ecosystem?

A forest ecosystem can be defined as a vast stretch of land that is covered by trees and different types of organisms. The component of any ecosystem that is living is considered to be the biotic component. In an ecosystem organism that produce their own food and are autotrophic in nature are called producers. They are considered to be a biotic component of the ecosystem. The decomposers are the microbes and bacteria that degrade the organic matter into simpler forms. They are also living and hence categorized as the biotic component of the ecosystem. The consumers are the organisms that are unable to produce their own food and they depend on other organisms to fulfil their nutritional requirements. 

Hence, the correct option is D.