Final answer:
The prefrontal cortex is the most likely brain structure active while Dante's working memory is engaged, as it is primary in holding and manipulating short-term information.
Step-by-step explanation:
Dante is engaging his working memory as he reorders his notecards alphabetically. Working memory, which refers to the ability to hold and manipulate information over short periods, is primarily a function of the prefrontal cortex. The prefrontal cortex is the area of the brain that is most active during tasks that involve working memory. While memory storage and retrieval involve multiple brain regions, the hippocampus and the amygdala are more closely associated with long-term memory formation and the storage of memories, respectively. The hippocampus plays a key role in the formation of new memories and spatial recognition, whereas the amygdala is crucial for emotional memory processing. Another important area of the brain that contributes to memory is the thalamus, which acts as a relay station, processing and transmitting information to various parts of the brain. However, when it comes to working memory specifically, the prefrontal cortex is the most active and relevant brain structure. So, the answer to Dante's task is c) Prefrontal cortex.