The way in which the author develops a feeling of sadness regarding the provided situation would be:
A). He sets the story on a rainy day.
- "Setting"(description of time, as well as, place) always play a vital role in providing the background to the readers regarding the narrative.
- This helps them know the mood of the story and the perspective to effectively understand the narrative.
- In the given excerpt, the setting of the narrative with a rainy day to denote the challenging situation(hitting rain) of Gregor followed by descriptive words like "troubled, horrible, stiff, pain, etc." allows the readers to know the grief or unhappiness that Gregor is undergoing.
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