Answer:
C. The darkness makes the setting feel disturbing.
Step-by-step explanation:
The setting in this passage helps to create suspense because the darkness as described made the setting disturbing and gave it a sense of impending doom.
The description here in the opening paragraph "During the whole of a dull. dark and soundless day..." makes the setting have a dangerous feel because it gives the sense that danger is lurking nearby and anything can happen.