Final answer:
Mr. Nuttel's lack of information and Vera's deceitful story lead to heightened anxiety for Mr. Nuttel when men arrive at the open window. The correct option is b) Heightened anxiety.
Step-by-step explanation:
The knowledge disparity between Vera and Mr. Nuttel in the story leads to heightened anxiety on the part of Mr. Nuttel concerning the men's arrival at the open window. Vera, being privy to certain information that Mr. Nuttel lacks, manipulates the situation to create a false narrative.
The disparity in knowledge, wherein Vera has an upper hand, causes Mr. Nuttel to misunderstand the situation, leading to an increase in his anxiety and eventual distress when the men arrive, as he believes a tragic backstory introduced by Vera to be true.