Question: Information: - Excavata is a major supergroup of unicellular organisms belonging to the domain Eukaryota . Introduced by Thomas Cavalier - Smith in 2002 as a new phylogenetic category , it contains a variety of free - living and symbiotic forms , and also includes some important parasites of humans . Excavates were formerly considered to be included in the now obsolete Protista kingdom . They are classified based on their flagellar structures , and they are considered to be the oldest members ( basal lineage ) of flagellated organisms . - The University of Oxford (informally Oxford University or simply Oxford) is a collegiate research university located in Oxford, England, United Kingdom. While having no known date of foundation, there is evidence of teaching as far back as 1096, making it the oldest university in the English-speaking world and the world's second-oldest university in continuous operation. It grew rapidly from 1167 when Henry II banned English students from attending the University of Paris. After disputes between students and Oxford townsfolk in 1209, some academics fled northeast to Cambridge where they established what became the University of Cambridge. The two "ancient universities" are frequently jointly referred to as "Oxbridge". - Protist is an informal term for any eukaryotic organism that is not an animal, plant or fungus. The protists do not form a natural group, or clade, but are often grouped together for convenience, like algae or invertebrates. In some systems of biological classification, such as the popular 5-kingdom scheme proposed by Robert Whittaker in 1969, the protists make up a kingdom called Protista, composed of "organisms which are unicellular or unicellular-colonial and which form no tissues." - Thomas (Tom) Cavalier-Smith, FRS, FRSC, NERC Professorial Fellow (born 21 October 1942), is a Professor of Evolutionary Biology in the Department of Zoology, at the University of Oxford. His research has led to discovery of a number of unicellular organisms (protists) and definition of taxonomic positions, such as introduction of the kingdom Chromista, and other groups including Chromalveolata, Opisthokonta, Rhizaria, and Excavata. He is well known for his system of classification of all organisms. - The Rhizaria are a species-rich supergroup of mostly unicellular eukaryotes. A multicellular form has also been described. This supergroup was proposed by Cavalier-Smith in 2002. Being described mainly from rDNA sequences, they vary considerably in form, having no clear morphological distinctive characters (synapomorphies), but for the most part they are amoeboids with filose, reticulose, or microtubule-supported pseudopods. Many produce shells or skeletons, which may be quite complex in structure, and these make up the vast majority of protozoan fossils. Nearly all have mitochondria with tubular cristae. - Chromalveolata is a eukaryote supergroup present in a major classification of 2005, then regarded as one of the six major groups within the eukaryotes. It is a refinement of the kingdom Chromista, first proposed by Thomas Cavalier-Smith in 1981. Chromalveolata was proposed to represent the organisms descended from a single secondary endosymbiosis involving a red alga and a bikont. The plastids in these organisms are those that contain chlorophyllc. Given the information above, choose from the list below the object entity that exhibits the relation 'parent taxon' with the subject 'excavata'. Choices: - chromista - eukaryote - paris - plant - protist - rhizaria
Answer:
eukaryote