Which of the following was NOT a reason for the Mali Empire's decline? Mansa Musa's gold donations during his hajj New gold mines were discovered outside of the Mali Empire The black plague decimated 2/3 of Timbuktu, Gao, and Djenne Mansa Musa's children and grandchildren's fights led to civil war

The statement "The black plague decimated $2/3$ of Timbuktu, Gao, and Djenne" was NOT a reason for the Mali Empire's decline. The Black Plague primarily affected Europe and parts of Asia, and there is no historical evidence to suggest that it had a significant impact on the population of the Mali Empire. The other reasons listed, such as Mansa Musa's gold donations during his hajj, the discovery of new gold mines outside of the Mali Empire, and internal conflicts among Mansa Musa's descendants, were more directly related to the empire's decline.