Final answer:
In the story 'The Feather Pillow,' the young bride experiences 'hot and cold shivers' due to physical influences related to her answers to Aylmer's questions about her sensations.
Step-by-step explanation:
In the story 'The Feather Pillow,' the young bride's 'hot and cold shivers' are caused by the physical influences she experiences when she answers Aylmer's questions about her sensations.
She begins to feel strange sensations creeping through her veins and tingling, which she suspects might be due to the fragrant air she breathes in or the food she consumes.
These sensations intensify when she looks in the mirror and sees her pale face with the red birthmark on her cheek.
This causes her to have 'hot and cold shivers,' indicating a mixture of fear, discomfort, and anxiety.