The answer is the last choice, commonality.
In the US, Democrats and Republicans beliefs to two major political parties
Answer:
A location among Indian coast trade routes ( A )
Explanation:
East African cities like Kilwa and Mombasa enjoyed and benefited from the Indian coast trade routes where they were able to carry out trades with east Asia especially China successfully.
The Indian ocean coast trade routes connected southeast Asia , Arabia and India. the goods the east African cities traded and benefited immensely from were: slaves , Ivory, Gold, Ivory, leopard skin and tortoise shells, but most of the trades were on slaves been sold from East Africa along the trading route .
other regions connected via the trading route traded on goods like ceramics wine gold and ivory.
