he has become a student of one of the most _________ leaders in history.

tyrannical, comport, or debase

he has become a student of one of the most tyrannical leaders in history.

he has become a student of one of the most tyrannical leaders in history.

To determine which word, "tyrannical," "comport," or "debase," best fits the sentence, we need to understand the meaning of each word.

1. "Tyrannical" describes someone who exercises power in a cruel and oppressive manner.
2. "Comport" means to behave or conduct oneself in a particular manner, usually in accordance with established norms or standards.
3. "Debase" means to reduce in quality or value, especially morally or intellectually.

Based on the context of the sentence, we are looking for a word that describes a powerful leader in a negative or unfavorable way. The word that fits this criterion is "tyrannical." Therefore, the correct completion of the sentence would be: "he has become a student of one of the most tyrannical leaders in history."

To make a choice without context, we would need additional information about the leader's behavior, style of leadership, or reputation.