The following excerpt comes from a description of the kingdom of Ghana, written by an 11th-century Arab from Spain, Al-Bakri:
On every donkey-load of salt when it is brought into the country their king levies one golden dinar and two dinars when it is sent out. … The best gold is found in his land comes from the town of Ghiyaru, which is eighteen days' traveling distance from the king's town over a country inhabited by tribes of the Sudan…
Source: Public Domain

Question

The following excerpt comes from a description of the kingdom of Ghana, written by an 11th-century Arab from Spain, Al-Bakri:
On every donkey-load of salt when it is brought into the country their king levies one golden dinar and two dinars when it is sent out. … The best gold is found in his land comes from the town of Ghiyaru, which is eighteen days' traveling distance from the king's town over a country inhabited by tribes of the Sudan…
Source: Public Domain

anonymous · Answer

What inference about ancient Ghana does the excerpt support?

 The king of Ghana controlled distant gold mines.

 Crossing Ghana could require more than two weeks.

 Ghanaians transported salt by foot.

 Ghanaians worked with Sudanese tribes to get gold.