Explanation:

Biotic Components

Option (d) is correct: Biotic component of ecosystem consist of living components. The different biotic components are connected through food and a number of other relations. The following three main types are :

! Producers: Autotrophic organisms are called producers. They are green plants and certain bacteria. They are capable of synthesizing organic food from inorganic raw materials with the help of solar energy. They provide food, shelter and oxygen to the living organisms. Some of the examples of producer are herbs, shrubs, grasses, phytoplanktons and trees.

! Consumers: They are animals that feeds on other organisms. They are also called heterotrophs. They are divided into two types, herbivorous and carnivorous. Herbivores obtain their food directly from green plants or producers. So, they are also known as primary consumer. For examples, deer feed on grass. Here, deer is a primary consumer and grass is a producer. Carnivores feed on herbivores. For example, jackal feed on herbivorous animals like deer, goat etc. Here, jackal is a primary carnivorous or secondary consumer. Here again, these secondary consumers are eaten by top consumers like lion, tiger etc. This are known as top consumers because they are not eaten by other animals.

! Decomposers: They feed on dead bodies of organisms and organic wastes of living organisms. They absorb some of the product while release most of the inorganic compounds into environment. These inorganic compounds are used by the producers to produce food. Some of the examples of decomposers are maggots, bacteria, slugs, etc.