Final answer:
Christian's conversation with Roxanne echoes Shakespeare's balcony scene and is tragic due to Cyrano's self-sacrifice in love. Cyrano hides his feelings to help Christian woo Roxanne despite his deeper affections for her.
Step-by-step explanation:
When Christian speaks to Roxanne in a scene that echoes the balcony scene from Romeo and Juliet, it is considered 'tragic' because Cyrano, the true author of the words, must hide his own love for Roxanne while helping Christian woo her. Cyrano's actions illustrate a theme of self-sacrifice and unrequited love, which is a prevalent element in tragic literature.
Cyrano is willing to do this because of his deep affection for Roxanne and his belief that he himself is not worthy of her love due to his physical appearance, specifically his large nose. This dynamic creates a tragic situation where the person who truly loves Roxanne and can express it most eloquently must stand in the shadows, while someone else reaps the rewards of his poetic gift.