Answer:
The narrator does not trust what she has seen.
Step-by-step explanation:
This is the statement that supports the idea that the story is told by an unreliable narrator. The first thing we learn in this passage is that the woman is very sure of having seen someone who appeared to be a nurse. Nevertheless, when she discusses this with Agnes, she begins to doubt her own experience. She then tells us that maybe the woman was not a nurse, and she decides that she will not ask more questions. The fact that the narrator does not trust what she has seen shows that she is an unreliable narrator.