Which statement best describes indirect bilirubin?

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Indirect bilirubin is the unconjugated form that has not yet been conjugated in the liver. Because it is not water-soluble, it travels in the bloodstream bound to albumin and must be taken up by hepatocytes to be processed. In the liver, the enzyme UDP-glucuronosyltransferase conjugates bilirubin with glucuronic acid, producing a water-soluble conjugated (direct) bilirubin that is excreted into bile. Therefore, describing indirect bilirubin as unconjugated best captures its non-soluble, pre-conjugation state. The other statements reference properties of the conjugated form or its direct excretion into bile, which belong to direct bilirubin rather than indirect.