The correct options are
A Species composition
B Diversity
C Stratification
The heterotrophs are the organisms which depend on other organisms for food.They cannot prepare their own food.The heterotrophs are classified into three based on their method of obtaining food. They are
i) Holozoic: Animals feeding on large particles of food are called holozoic.
ii) Parasites: A parasite is an organism that lives on or in a host and gets its food from or at the expense of its host.
iii) Saprophytes: A saprophyte or saprotroph is an organism which gets its energy from dead and decaying organic matter.