The correct option is C Intensity of feeling a character has for another person to the character's concern that that intensity is not reciprocated
Option B captures the sentiment of the passage stating the shift in narrative where the narrator speaks of his emotions for Mattie, the depth and intensity with which he felt them. Then, his thoughts are put into check when he is concerned about the reciprocity of those feelings. He doesn't know if she feels the same way about him and that eats him up. There are no reservations in his mind, which vanished the moment he came in contact with her. Despite the doubt about Mattie's indifference towards him, he was sure about his own emotions and had no problem recognizing them. Though the elements of nature are mentioned and the narrator is vocal about being enthralled by Mattie's beauty, the narrative has nothing to do with it. Thus, options A,B and C are incorrect in this context.