To accurately determine what the underlined sentence in the excerpt suggests about Framton's character, it's essential to analyze the context of the sentence.
If the underlined sentence indicates that Framton is uncomfortable or anxious in social situations or reflects his nervousness or apprehension, then it would most closely align with the response:
"It suggests that Framton lacks courage in new situations."
However, without having the specific underlined sentence or additional context, it's also plausible that it could imply self-consciousness or unfamiliarity with his surroundings. But generally, in "The Open Window," Framton Nuttel is portrayed as an anxious and somewhat timid character, which supports the answer regarding his lack of courage in new environments.
If you have the exact underlined sentence, I can provide a more detailed analysis to confirm the best response.