Indigenous because in 1900, only 14% in Sub-Saharan Africa practiced Christianity, and 9% practiced Islam. That was during the colonial period. Hindu was practiced by the Indians, so the only logical answer is Indigenous.
North Africa has a Muslim majority for several centuries, yet sub-Saharan Africa has experienced a dramatic religious shift in the 20th century. In 1900, Christians (9%) and Muslims (14%) were a minority in sub-Saharan Africa, while 76% of the population followed African indigenous religions. Many of these religions were brought to the Americas through the slave trade and gave birth to African-American religions, such as candomblé and umbanda in Brazil, santeria in Cuba and voodoo in Haiti.
Answer: Their theory is called levels of processing. If we want to remember a piece of information, we should think about it more deeply and link it to other information and memories to make it more meaningful.
I am a muslim and that is not the true defenition of jihad. They are extremist groups who believe they are doing jihad. The true defenition of jihad is to struggle for the way of god. Hope this helps you from my personal view. :)