A. Lactulose is a non-absorbable disaccharide that helps reduce the absorption of ammonia in the intestines. By promoting the excretion of ammonia, it can lead to an improvement in the mental status of patients with hepatic encephalopathy. B. While improvement in mental status might contribute to better mobility, lactulose specifically addresses ammonia levels rather than directly improving physical mobility or the ability to ambulate. C. Lactulose does not have a direct effect on urine output. Its primary action is in the intestines, where it helps reduce ammonia levels, rather than affecting kidney function or urine production. D. Lactulose often causes an increase in bowel movements, leading to more liquid stools rather than a reduction. It works as an osmotic laxative, drawing water into the bowel to help facilitate the passage of stools.