Which syndrome is characterized by an inability to process galactose?

The correct choice is Galactosemia, which is characterized by an inability to properly process galactose, a type of sugar found in milk and other dairy products. This condition arises from a deficiency in one of the enzymes required for galactose metabolism, most commonly galactose-1-phosphate uridylyltransferase. When galactose is not adequately metabolized, it can build up in the body, leading to serious health complications, such as liver damage, cataracts, and cognitive impairment.

In the context of the other syndromes listed, Sanfilippo Syndrome, Hurler's Syndrome, and Hunter Syndrome are all types of mucopolysaccharidoses, which are related to the metabolism of glycosaminoglycans. These conditions do not involve an inability to process galactose but rather involve the accumulation of specific types of sugars due to enzyme deficiencies that affect different metabolic pathways. Therefore, Galactosemia stands out as the only syndrome in this question directly connected to the inability to process galactose.