Answer:
B. mysterious
Step-by-step explanation:
The word that best describes the tone of the excerpt is that it was mysterious.
According to the excerpt of The Fowl In The Pot by Stanley J. Weyman, a group of people arrived at a certain house at night and the house seemed "to be of rather greater pretensions".
Also, their guide was whispering to them as if there was something malevolent lurking around. The guide also proceeded to knock at the door "in a peculiar fashion" and when the group of people looked into the house, they saw a young woman who was bent over a fire and "crooning a lullaby while attending to a large black pot".