**Core Concept**
Anterograde amnesia refers to the inability to form new memories after a traumatic brain injury, stroke, or other pathological conditions. This type of amnesia is characterized by the inability to encode new information into long-term memory, making it difficult for individuals to learn new skills or recall events that occurred after the onset of the condition.

**Why the Correct Answer is Right**
Anterograde amnesia is typically associated with damage to the hippocampus, a structure in the temporal lobe that plays a crucial role in the formation of new memories. The hippocampus is essential for the consolidation of short-term memories into long-term memories, and damage to this region can result in the inability to form new memories. In addition, the diencephalon, particularly the mammillary bodies and the thalamus, also play a role in the formation of new memories. Damage to these structures can also contribute to anterograde amnesia.

**Why Each Wrong Option is Incorrect**
* **Option A:** Retrograde amnesia refers to the loss of memories that occurred before the onset of the condition, not the inability to form new memories. It is typically associated with damage to the temporal lobe and the hippocampus.
* **Option B:** Posterior cortical atrophy is a condition characterized by the degeneration of the posterior cortex, leading to difficulties with visual perception, spatial awareness, and language processing. It is not directly associated with the formation of new memories.
* **Option C:** Korsakoff's syndrome is a condition that can cause anterograde amnesia, but it is also characterized by a confabulatory state, where individuals fill in gaps in their memory with false information. While Korsakoff's syndrome can cause anterograde amnesia, it is not the only condition that does so.

**Clinical Pearl / High-Yield Fact**
The hippocampus is a critical structure for the formation of new memories, and damage to this region can result in anterograde amnesia. It is essential to consider the anatomical location of the damage when evaluating patients with memory impairments.

**Correct Answer:** D.