Final answer:
Mrs. Sommers' familiarity with her neighbors and the mention of different neighborhoods suggest that she lives in an urban area.
Step-by-step explanation:
To infer that Mrs. Sommers lives in an urban area, we can look at the information provided.
The fact that she selects a block where she is comfortable walking because she knows many of the people living on the street suggests that she has a level of familiarity with her neighbors.
This kind of familiarity is more commonly found in urban areas where people often interact with their neighbors on a regular basis
. Additionally, the mention of different neighborhoods and housing patterns in the late nineteenth century indicates that the story takes place in a city or urban setting.