The section that best supports the answer to Part A is D: "Does this make us mates I wonder, as I cross the fields towards home, but I know it doesn't." (Paragraph 69).
This line emphasizes Finn's feelings of sadness and uncertainty about his relationship with Gren, highlighting his awareness that despite their moments together, they might not truly be friends or 'mates.' This reflects Finn's emotional struggle regarding his place in Gren's social circle and the deeper connections he yearns for.