**Core Concept**
Korsakoff syndrome is a neurological disorder characterized by memory impairment, particularly anterograde amnesia, and confabulation. It is a complication of chronic alcohol abuse and typically results from thiamine deficiency.

**Why the Correct Answer is Right**
Korsakoff syndrome is primarily associated with the degeneration of the mammillary bodies and other parts of the limbic system, including the hippocampus and the fornix. This leads to impaired memory consolidation and retrieval, resulting in anterograde amnesia and the tendency to fill in memory gaps with confabulations. The patient's inability to form new memories (anterograde amnesia) is a hallmark feature of Korsakoff syndrome.

**Why Each Wrong Option is Incorrect**
* **Option A:** Confabulation is indeed a feature of Korsakoff syndrome, as patients attempt to fill in memory gaps with false information. This is a characteristic symptom of the disorder.
* **Option B:** Memory impairment is a fundamental aspect of Korsakoff syndrome, including both anterograde and retrograde amnesia. This option is incorrect because it is actually a feature of the condition.
* **Option D:** Wernicke's encephalopathy, a related condition, is characterized by a triad of confusion, ataxia, and ophthalmoplegia. While Korsakoff syndrome often follows Wernicke's encephalopathy, the two conditions have distinct clinical features.

**Clinical Pearl / High-Yield Fact**
Korsakoff syndrome is often considered a "hidden" disorder, as patients may appear to be alert and oriented but still exhibit significant memory impairment. This can lead to difficulties in diagnosis, as clinicians may not suspect the presence of Korsakoff syndrome based on the patient's apparent level of consciousness.

**Correct Answer: C. Wernicke's encephalopathy is a distinct condition.**