Final answer:
The correct answer is option b. Count de Guiche takes revenge on Christian by sending him to a dangerous mission with the Gascony Guards during the Siege of Arras, demonstrating his influence and desire for retribution in the play 'Cyrano de Bergerac' by Edmond Rostand.
Step-by-step explanation:
In the play Cyrano de Bergerac by Edmond Rostand, when Count de Guiche learns that Roxane has married Christian instead of him, he decides to get his revenge in a calculated manner. Although option A confronts the romanticized idea of a duel, and options C and D involve manipulation and betrayal that would fit well within the themes of the play, the correct choice is B.
Count de Guiche takes his revenge by sending Christian to the front lines of battle, specifically to a military group called the Gascony Guards, which was known to be involved in the most dangerous actions at the time of the Siege of Arras. This option not only demonstrates the count's power and influence but also his cold-heartedness and strategic thinking in matters of vengeance.