Final answer:
The influence of Islam in western Africa is exemplified by Mansa Musa’s pilgrimage to Mecca, showcasing the Mali Empire's wealth and religious commitment to Islam, and leading to the deeper Islamic cultural presence in regions like Timbuktu.
Step-by-step explanation:
The evidence of the influence of Islam in western Africa is most strongly showcased by a) Mansa Musa's pilgrimage to Mecca. Mansa Musa was the ruler of the Mali Empire in the 14th century, and he is perhaps the most famous for his pilgrimage, which demonstrated the wealth and the Islamic faith of Mali. During his journey in 1324-1325, Mansa Musa distributed vast amounts of gold, particularly in Cairo, which caused inflation there for over a decade. Upon his return, he brought back Muslim scholars, architects, and introduced Islamic educational structures such as mosques, universities, and libraries, especially in the city of Timbuktu, thus deepening the Islamic character of his empire.