The correct answer is A. terrified.
Embarrassment is a feeling of shame or discomfort caused by something that is considered to be improper or foolish. Humiliation is a feeling of extreme shame or degradation. Fear is a feeling of anxiety or dread caused by the expectation of danger. Terror is an extreme form of fear.
Agitated is a feeling of restlessness or anxiety. Courage is the ability to do something that is difficult or dangerous, despite fear. Reckless is acting without thinking about the consequences.
In the analogy, embarrassed is to humiliated as frightened is to terrified. This is because embarrassment is a milder form of humiliation, just as fear is a milder form of terror. Agitated, courageous, and reckless are not related to embarrassed and humiliated in the same way.