Pluto has recently been demoted to 'dwarf planet' because it does not meet one or more of the following criteria of a planet : 1. A planet should orbit around the sun. 2. A planet should have sufficient mass, so that it assumes a nearly round shape. 3. A planet must hav e cleared its neigh bourhood around its orbit. Select the correct answer using the codes given below:

In 2006, the International Astronomical Union (IAU) established three criteria for a celestial body to be classified as a planet: (1) it must orbit the Sun, (2) it must have sufficient mass to assume a nearly round shape (hydrostatic equilibrium), and (3) it must have cleared the neighborhood around its orbit [c1, t3, t8]. Pluto meets the first two criteria as it orbits the Sun and is spherical [t4, t5]. However, it was demoted to 'dwarf planet' because it failed the third criterion; it shares its orbital path with other objects in the Kuiper Belt and crosses the orbit of Neptune [c1, t4, t9]. Since the question asks which criteria Pluto does *not* meet, only statement 3 is correct. Statements 1 and 2 are criteria that Pluto successfully fulfills [t5, t8].

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 2: The Solar System > Kuiper Belt, Pluto, and Charon > p. 33