Final answer:
The Kingdom of Aksum enhanced trade in Africa through the construction of extensive trade networks and a prosperous port, leveraging its strategic position by the Red Sea to trade luxury goods and becoming a key player in the global trade system.
Step-by-step explanation:
The Kingdom of Aksum enhanced trade in Africa during the early Middle Ages through the construction of extensive trade networks and a prosperous port. This expansive trade network was centered on the Red Sea, which allowed Aksum to trade luxury goods like gold, ivory, and spices such as frankincense and myrrh with Egypt, the eastern Mediterranean, and the Arabian Peninsula. During the reign of King Ezana, Aksum's trade with the African interior expanded considerably, allowing for increased wealth and power. Aksum also established itself on the Indian Ocean trade network, facilitating exchange with the Middle East, China, and East and Southeast Asia.
Aksum's prosperity was due not only to its strategic location adjacent to the Red Sea but also because it actively participated in and promoted long-distance trade. This made Aksum an integral part of the global trade system during the early medieval period, expanding its influence and bringing different cultures and economies into contact. Hence, the correct answer to the question of how the Kingdom of Aksum enhanced trade in Africa is 'b) Through the construction of extensive trade networks and a prosperous port'.