Q:Information:  - In biology, an organism is any contiguous living system, such as an animal, plant, fungus, archaeon, or bacterium. All known types of organisms are capable of some degree of response to stimuli, reproduction, growth and development and homeostasis. An organism consists of one or more cells; when it has one cell it is known as a unicellular organism; and when it has more than one it is known as a multicellular organism. Most unicellular organisms are of microscopic scale and are thus loosely described as microorganisms. Humans are multicellular organisms composed of many trillions of cells grouped into specialized tissues and organs.  - Cyathus stercoreus, commonly known as the dung-loving bird's nest, is a species of fungus in the genus "Cyathus", family Nidulariaceae. Like other species in the Nidulariaceae, the fruiting bodies of "C. stercoreus" resemble tiny bird's nests filled with eggs. The fruiting bodies are referred to as splash cups, because they are developed to use the force of falling drops of water to dislodge and disperse their spores. The species has a worldwide distribution, and prefers growing on dung, or soil containing dung; the specific epithet is derived from the Latin word "stercorarius", meaning "of dung".  - Cyathus is a genus of fungi in the Nidulariaceae , a family collectively known as the bird 's nest fungi . They are given this name since they resemble tiny bird 's nests filled with `` eggs '' , structures large enough to have been mistaken in the past for seeds . However , these are now known to be reproductive structures containing spores . The `` eggs '' , or peridioles , are firmly attached to the inner surface of this fruit body by an elastic cord of mycelia known as a funiculus . The 45 species are widely distributed throughout the world and some are found in most countries , although a few exist in only one or two locales . Cyathus stercoreus is considered endangered in a number of European countries . Species of Cyathus are also known as splash cups , which refers to the fact that falling raindrops can knock the peridioles out of the open - cup fruit body . The internal and external surfaces of this cup may be ridged longitudinally ( referred to as plicate or striate ) ; this is one example of a taxonomic characteristic that has traditionally served to distinguish between species . Generally considered inedible , Cyathus species are saprobic , since they obtain nutrients from decomposing organic matter . They usually grow on decaying wood or woody debris , on cow and horse dung , or directly on humus - rich soil . The life cycle of this genus allows it to reproduce both sexually , with meiosis , and asexually via spores . Several Cyathus species produce bioactive compounds , some with medicinal properties , and several lignin - degrading enzymes from the genus may be useful in bioremediation and agriculture . Phylogenetic analysis is providing new insights into the evolutionary relationships between the various species in Cyathus , and has cast doubt on the validity of the older classification systems that are based on traditional taxonomic characteristics  - Nidula is a genus of fungi in the family Agaricaceae. Their fruit bodies resemble tiny egg-filled birds' nests, from which they derive their common name "bird's nest fungi". Originally described in 1902, the genus differs from the related genera "Cyathus" and "Crucibulum" by the absence of a cord that attaches the eggs to the inside of the fruit body. The life cycle of this genus allows it to reproduce both sexually, with meiosis, and asexually via spores. Species in this genus produce a number of bioactive compounds, including 4-("p"-hydroxyphenyl)-2-butanone, a major component of raspberry flavor and insect attractor used in pesticides.  - A genus ( genera) is a taxonomic rank used in the biological classification of living and fossil organisms in biology. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus.  - Binomial nomenclature (also called binominal nomenclature or binary nomenclature) is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages. Such a name is called a binomial name (which may be shortened to just "binomial"), a binomen or a scientific name; more informally it is also called a Latin name. The first part of the name identifies the genus to which the species belongs; the second part identifies the species within the genus. For example, humans belong to the genus "Homo" and within this genus to the species "Homo sapiens". The "formal" introduction of this system of naming species is credited to Carl Linnaeus, effectively beginning with his work "Species Plantarum" in 1753. But Gaspard Bauhin, in as early as 1623, had introduced in his book "Pinax theatri botanici" (English, "Illustrated exposition of plants") many names of genera that were later adopted by Linnaeus.    Given the information above, choose from the list below the object entity that exhibits the relation 'parent taxon' with the subject 'cyathus'.  Choices: - agaricaceae  - animal  - bird  - cyathus  - fungi  - homo  - nidula  - nidulariaceae
A:
agaricaceae