Answer:
High amounts of fat in the stools.
Step-by-step explanation:
Based on the information provided, a sign of Nikki's disease is high amounts of fat in the stools. Lipase is an enzyme produced by the pancreas that helps to digest fats in the body. If the production of lipase is impaired, this can lead to undigested fats being present in the stools. This can be observed through the presence of fatty or greasy stools, which may have a pale or light-colored appearance. The other options listed, such as lack of saliva in the mouth, low C-reactive protein in blood, and ulcer formation in the stomach, are not directly related to the impaired production of lipase in the pancreas.