Answer:
D. It describes a change in the atmosphere.
Explanation:
Neil Gaiman's short story "Click-Clack the Rattlebag" revolves around a horror story told by a young boy to his sister's boy friend. Through the boy friend who is the narrator of the story, we can understand the theme of the story of how things are not how they originally seem to be.
In the given line from the story, the narrator talks about how the atmosphere changed from the small kitchen to the hallway. While the kitchen was "warm and cosy", the hallway was much more "chilly and draughty and dark". This, added with the scary story-telling, develops the suspense in the story.
Thus, the correct answer is option D.