Final answer:
The most indicative sign of a trafficking victim in the options provided is a person who appears fearful or submissive, as this kind of body language is often seen in trafficking victims.
Step-by-step explanation:
Body language is a critical indicator when identifying whether a person might be a victim of trafficking. Among the options provided, C. A person who appears fearful or submissive would certainly raise a red flag. Victims of trafficking often display body language that suggests discomfort or unease such as avoiding eye contact, exhibiting fearful expressions, and having a closed-off body posture, like crossed arms or hunched shoulders. They may also appear controlled or monitored by another person and show signs of not being free to move or speak for themselves. It is important for observers to be mindful of such nonverbal cues along with the context to identify individuals who may be in need of help.