Final answer:
Greek Charlie is reputed for straightening hair, indicating a skill that aligns with the cultural importance of hair in both African and Ancient Greek societies.
Step-by-step explanation:
The information shared through the "black grape-vine" about Greek Charlie pertains to c) Reputation for straightening hair. In various cultures, including African and African diasporic cultures, hairstyles and hair maintenance hold significant importance. They are often tied to one's social status and identity. In Ancient Greek society, beauty standards held blonde hair in high regard, suggesting that color and styling played vital roles in these cultural contexts. Greek Charlie's reputation for straightening hair would, therefore, be a noteworthy skill worth sharing through the grapevine, given the importance of hairstyles across cultures.