A stoic person is best described as?

A stoic person is characterized by their ability to remain calm and unperturbed regardless of external circumstances. This means that they do not allow emotions, passions, or feelings to dictate their responses or behavior. The essence of stoicism, both as a philosophical doctrine and as a personal trait, emphasizes maintaining composure and rationality in the face of adversity or emotional turmoil. Therefore, the definition of being "not affected by passion or feeling" accurately captures the core of what it means to be stoic.

The other choices, while they may describe certain attributes, do not align with the fundamental definition of stoicism. Being overly preoccupied suggests a lack of focus or an excessive concern about minutiae, which contradicts stoic calmness. Living in seclusion indicates withdrawal from social interaction and does not reflect the composed presence stoics maintain in the face of challenges. Lastly, being artful, cunning, or deceitful implies manipulation and emotional engagement, which is the opposite of the stoic ideal of emotional detachment and rationality. Thus, the correct choice emphasizes the stoic virtue of emotional resilience and control.