Final answer:
Titus's true color, which is a metaphor for his true character, is most likely revealed through his behavior. This would be consistent with literary tropes where personal challenges and reactions to circumstances showcase a character's true nature.
Step-by-step explanation:
The phrase 'true color' is usually a figure of speech that refers to one's true character or intentions becoming evident through actions or words. Without more context, it is not clear who Titus is, but the options given (eye color, voice, scars, behavior) suggest a narrative or literary character. In literature, character revelations often come through behavior (d), which can encompass actions, speech, and decisions that signify someone's true personality or identity.
In this context, it seems likely that the question might be exploring themes from a narrative where an individual like Titus is dealing with personal challenges, possibly including the cruelty of his enslaver, the fact that he had lived in free states, or the fact that his family would be torn apart. The events or emotional reactions stemming from these situations could reveal his inner character through his behavior.
Again, without further context, it is difficult to pinpoint the precise moment that gave away Titus's true color, but based on common literary tropes, it would be reasonable to infer that his behavior would be the most telling sign of his character.