The unpleasant feeling passed and she glanced guardedly up ,at him. He was walking unmarked in moonlight, innocent of her reaction to him. She felt then - this thought had come to her before - that there might be more to him than she had imagined. She felt ashamed she had never thanked him for the help he had given her father.
Her unpleasant feeling passed when

Options

A. He did not take any notice of her
B. The moonlight was beautiful
C. She realized her sense of shame
D. She looked carefully at him