In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.

Question: When did the time period in which Anomocephaloidea existed begin? Passage:Anomocephaloidea is a clade (evolutionary grouping) of anomodont therapsids that existed in Gondwana during the Middle Permian and includes two species, Anomocephalus africanus from South Africa and Tiarajudens eccentricus from Brazil, both of which are characterized by large body size and teeth that fit tightly together or occlude. Anomocephaloidea is among the most basal groups of anomodonts, the other being Venyukovioidea, which differs in being a Laurasian clade of mostly small-bodied species. Anomocephaloidea was named in 2011 with the discovery of Tiarajudens; Anomocephalus had been known since 1999, but was unique among anomodonts until Tiarajudens was described. Both Anomocephalus and Tiarajudens were herbivores, although the latter possessed a pair of saber-like canine teeth that may have been used in display or combat with other individuals of the same species. Although Anomocephaloidea was short-lived and had a limited geographic distribution, it was part of a larger evolutionary radiation of anomodonts in the Middle Permian characterized by the evolution of a diverse array of new morphological characteristics and ecological roles, and that would later lead to the rise of Dicynodontia, the largest clade within Anomodontia and one of the most successful groups of tetrapods in the Permian.
Links: a. Venyukovioidea b. Guadalupian c. Herbivore d. Dicynodont
b