Four words are shown below: Facultative obligate saprophytes parasites These words can be used in the basis of P Q R and S to complete the sentence below. Organisms that depend on living plants and animals for the nutritional requirements are known as.... P... Parasites, which depend on the nutrition entirely on other living organisms, are known as...Q... or total parasites and those which depend for these requirements partially on other living organisms are called...R...or partial parasite on the other hand the plants which depend on dead or rotten organic remains of plants and animals are called...S...

Explanation

Parasite is an organism that lives in or on an organism of another specie (its host) and benefits by deriving nutrients at the other's expense. An obligate parasite or holoparasite is a parasitic organism that can not complete its life-cycle without exploiting a suitable host. If an obligate parasite can not obtain a host, it will fail to reproduce. Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed organic matter. It occurs in saprotrophs and is most often associated with fungi and soil bacteria. A facultative parasite is an organism that may resort to parasitic activity but does not absolutely rely on any host for completion of its life cycle. Examples of facultative parasitism occur among many species of fungi, such as family members of the genus Armillaria. So, Option b is the correct answer.