Final answer:
Montag is conflicted and uneasy, experiencing a profound internal struggle and turmoil, as opposed to feeling joy, calmness, or direct anger.
Step-by-step explanation:
The best description of Montag's emotional state when he runs into Beatty at the firehouse after reading to Mildred and her friends would be that Montag is conflicted and uneasy. The passage provided indicates a tumult of emotions within him, including suffering, confusion, and a torrent of evolving sentiments. Instead of relief or indifference, Montag is experiencing a profound internal struggle that reflects fear, uncertainty, and confusion regarding his actions and the world around him. This is demonstrated by phrases such as "a dammed-up torrent of emotion" and "caught glimpses into himself, into unlit darkness of soul," suggesting a profound inner turmoil not consistent with joy, calmness, or direct anger.