Answer:
The correct answer is C. Axum. Tolls collected from the flow of gold and salt helped to build the kingdom of Axum, which was located in what is now Ethiopia and Eritrea. This is supported by the information found on the website metmuseum.org, which states that trans- Saharan trade linked the Mediterranean economies that demanded gold and could supply salt to the sub- Saharan kingdom of Axum from the seventh to the eleventh century.
Step-by-step explanation:
The kingdom of Axum was located in what is now Ethiopia and Eritrea. It was established in the first century CE and prospered due to its location at the crossroads of the Mediterranean and Indian Ocean trade routes. Tolls collected from the flow of gold and salt helped to build the kingdom of Axum, and trans- Saharan kingdom from the seventh to the eleventh century. This is supported by the information found on the website metmuseum.org.