Which sentence in the passage can be used to conclude Eris is a dwarf planet and not a planet.

Explanation:

Since the passage is not mentioned in the question. We can discuss this in general sense.

Eris is the second largest dwarf planet in the Solar system. It resides in the Kuiper belt. Kuiper belt is a thick belt of rocky and icy objects after the orbit of the Neptune.

In 2006, International Astronomical Union (IAU) formulated three conditions that must be fulfilled by an object to be called a planet. These are:

1. It must orbit around a star (In our case its the Sun)

2. It must be spherical in shape as a result of its gravity.

3. It must clear its neighborhood. That means it should be the gravitationally dominant body in the neighborhood.

Now, as far as Eris is concerned, it fulfills the first two criteria: it orbits the Sun and is spherical in shape. But it doesn't clear its neighborhood. It resides in the Kuiper belt and there are a lot of rocky objects of comparable size in its neighborhood.