Final answer:
Balthazar disobeys Romeo by bringing him false news of Juliet's death without verifying the information, leading to the tragic conclusion of the play.
Step-by-step explanation:
In William Shakespeare's Romeo and Juliet, Balthazar, Romeo's servant, disobeys his master in Act 5 by indirectly causing Romeo to believe that Juliet is dead. Although Balthazar does not have a direct order from Romeo regarding the news, he brings the information of Juliet's supposed death to Romeo in Mantua, despite the fact that he is not fully aware of the plan devised by Friar Lawrence to fake Juliet's death. This misinformation spurs Romeo to purchase poison and eventually leads to the tragic conclusion of the play, where both Romeo and Juliet die. In this sense, Balthazar disobeys Romeo by not verifying the truth of Juliet's death and by not adhering to Romeo's implicit trust in his service, which expected careful and truthful communication.