Substance cap x has a fixed volume, and the attraction between its particles is strong. Substance Y has widely spread out particles and can be compressed. What can most likely be concluded about these substances?

Substance X has a fixed volume and strong attractions between its particles, which are characteristics of a solid. Substance Y has widely spaced particles and can be compressed, indicating a gas-like state; among the choices, plasma is the gas-like state. Therefore, the best conclusion is that X is a solid and Y is a plasma.

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