The Great Zimbabwe was the center of a huge trading empire.

the home of Shaka and his powerful army.

where the remains of the earliest humans were found.

Correct answer is the center of a huge trading empire.

Explanation:

The center of a huge trading empire is the correct answer because it refers to a huge empire that was a center of trade in the region between 11th and 15th Century.

B is not correct as Shaka Zulu was a military leader on the soil of todays South Africa, known as Zulu Kingdom.

C is not correct as the first hominid named Lucy was found in Ethiopia.

the answer is c. according to past decisions, free speech is not unlimited.