Question

which other celestial body is roughly the same size as eris?
triton
pluto
neptune
dysnomia

Explanation:

Eris is a dwarf planet in the outer solar system. Among the options, Pluto (also a dwarf planet) has a diameter very close to Eris—both are roughly 2300-2400 km in diameter. Triton is Neptune’s moon (~2700 km, larger), Neptune is a gas giant (much bigger), and Dysnomia is Eris’s small moon (not comparable in size).

Answer:

Pluto