Without the specific underlined sentence provided, it's difficult to give a precise answer. However, based on the context of H.H. Munro's "The Open Window," I can suggest that the most fitting option might be:
"It suggests that Framton is slightly self-conscious about his shyness."
This is because Framton Nuttel is portrayed as a nervous and anxious character, particularly in social situations, which points to a sense of self-consciousness. If you have the specific sentence that is underlined, feel free to share it for a more accurate analysis!