Answer :
Answer:
After Eris was discovered, they had to decide whether Eris was a planet or not. If they decided it wasn't a planet, they had to also decide whether Pluto should be counted as a planet since Eris and Pluto were quite similar. They were the same size, and they were both part of the Kuiper Belt.
Explanation:
Planets are the celestial bodies that are not fixed. Pluto should be counted as a planet was a question as both Pluto and Eris were similar.
What are Pluto and Eris?
Pluto is now considered a dwarf planet and is found in the Kuiper belt that is present beyond the planet, Neptune. Similarly, Eris is also a dwarf planet.
Eris is the second-largest dwarf planet and is very similar to Pluto. The discovery of Eris questioned whether Pluto should be considered a planet.
Both the planets Pluto and Eris were similar in size and were part of the Kuiper Belt leading to the question of whether they should be a planet or not.
Therefore, option d. Pluto and Eris are very similar.
Learn more about Eris here:
https://brainly.com/question/15105153