Ninety-nine percent of all the matter that can be observed in the universe exists as

For the answer to the question above, the answer is plasmas.
Plasma is a form of matter in which many of the electrons wander around freely among the nuclei of the atoms. Plasma has been called the fourth state of matter, the other three being solid, liquid, and gas. The electrons in a solid, liquid, or gaseous sample of matter stay with the same atomic nucleus.
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