The speaker becomes angry with the raven primarily because it replies "nevermore" when he asks if he will be reunited with Lenore. This response reinforces his despair and hopelessness regarding his lost love, which contributes to his frustration and anguish. The raven's persistent negative responses serve as a reminder of his sorrow and loss, ultimately leading to the speaker's emotional breakdown. Thus, the correct answer is:
It replies "nevermore" when the speaker asks if he will be reunited with Lenore.