The provided text is a solution to multiple-choice questions about the history of ancient African kingdoms and trade routes. What are the questions that were answered?

here are the answers to the multiple-choice questions:

III. Choose the correct answer from the given alternatives

18. Which of the following was the main factor that contributed to the greatness of ancient Ghana?

    • Answer: A. The Trans-Saharan trade
    • Explanation: Ancient Ghana's power and wealth were largely based on its control of the Trans-Saharan trade routes, particularly the gold and salt trade.

19. Ancient Ghana came to an end in 1076 when the Islamic Empire of Almoravids invaded and captured its capital:

    • Answer: C. Kumbi Saleh
    • Explanation: The Almoravids captured Kumbi Saleh, the capital of ancient Ghana, in 1076, leading to the empire's decline.

20. Which of the following European country reached the Congo first?

    • Answer: C. Portugal
    • Explanation: Portuguese explorers, led by Diogo Cão, were the first Europeans to reach the mouth of the Congo River in the late 15th century.

21. Which of the following Swahili city-states became the main center of the East African gold and ivory trade?

    • Answer: D. Kilwa
    • Explanation: Kilwa was a dominant Swahili city-state that controlled much of the trade in gold and ivory along the East African coast.

22. The Hausa city-states emerged between 1000 and 1200AD in the present day:

    • Answer: C. Nigeria
    • Explanation: The Hausa city-states were located in what is now northern Nigeria and southern Niger.

23. All of the following were factors for the decline of Mamluks power except?

    • Answer: C. cattle plague
    • Explanation: While corruption, religious differences (especially with the rising Ottoman Empire), and droughts could contribute to the decline of an empire, a specific "cattle plague" is less commonly cited as a primary systemic factor for the overall decline of Mamluk power compared to political instability, economic shifts, and military threats.

24. Who was the greatest king of Mali who made a pilgrimage to Mecca in 1324?

    • Answer: C. Mansa Musa
    • Explanation: Mansa Musa is renowned for his extravagant pilgrimage to Mecca in 1324, which showcased the immense wealth of the Mali Empire.

25. The first phase of Trans-Atlantic Slave Trade, was known as the:

    • Answer: A. Monopolistic slave trade
    • Explanation: The early period of the Trans-Atlantic Slave Trade was characterized by European monarchs granting monopolies to specific companies or individuals to control the trade.