Q. With reference to the reclassification of celestial bodies by the International Astronomical Union (IAU), why is Pluto classified as a Dwarf Planet rather than a primary planet?

[A] It does not possess enough mass to assume a nearly round shape.

[B] It orbits a larger planet rather than circling the Sun directly.

[C] It has not cleared the neighborhood of debris surrounding its orbit.

[D] It is composed primarily of ice and dust rather than rocky or metallic minerals.

Answer: C
Notes:

Explanation:

According to the IAU, a planet must meet three criteria: it must orbit the Sun, be nearly round, and have cleared the neighborhood of its orbit. Pluto fails the third criteria as it shares its orbital path with other Kuiper Belt objects.

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