Content Development: Whole Paragraphs

In the following, identify the type of content development used in the paragraph below, select the corresponding multiple-choice item below (you may have to scroll to see all of the items), and then press the Click here ... button. Remember: few paragraphs will be a "pure" type but have other types mixed in. To review content types, see (opens in a separate browser).

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Discovered in 1930, Pluto was originally deemed to be the ninth planet from the Sun. Its status as a major planet fell into question following further study of it and the outer Solar System over the ensuing 75 years. Starting in 1977 with the discovery of the minor planet 2060 Chiron, numerous icy objects similar to Pluto with eccentric orbits were found. The most notable of these was the scattered disc object Eris, discovered in 2005, which is 27% more massive than Pluto. The understanding that Pluto is only one of several large icy bodies in the outer Solar System prompted the International Astronomical Union to define formally in 2006 what it means to be a "planet." This definition excluded Pluto and reclassified it as a member of the new "dwarf planet" category (and specifically as a plutoid). Astronomers who oppose this decision hold that Pluto should have remained classified as a planet, and that other dwarf planets and even moons should be added to the roster of planets along with Pluto.