Final answer:
The primary aspect of psychological suspense in 'The Pit and the Pendulum' is the emphasis on madness, as it contributes to an aura of uncertainty and creates a gripping, suspenseful atmosphere.
Step-by-step explanation:
In Edgar Allan Poe's 'The Pit and the Pendulum,' the dominating aspect of psychological suspense is d) Emphasis on madness. The protagonist's descent into madness and tormented mental state is a key part of the suspense and uncertainty that characterizes the story. Readers are continuously on edge due to the protagonist's unpredictable mental state, irrational fears, and the eerie, unsettling atmosphere that these elements create. This is not a story marked by admirable, heroic figures (option c), nor does it heavily rely on a fantasy-based plot (option a). Its writing style is also not necessarily plain and simple (option b), but rather detailed and descriptive, further emphasizing mental instability and lending to the psychological suspense.
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