What is the "African dust" made of that is described in the documentary that swirls up in the winds of Africa and travel across the Atlantic Ocean as a sandstorm to South America and the Amazon rainforest?

The correct answer to this question is the following.

Although there are no options attached, we can say the following.

Unfortunately, you did not attach the documentary, the name of it, or a link to it. Without that important information, we do not know what is the content of the video.

However, trying to help you, we did some research and can comment on the following general terms.

The African Dust is a giant dust cloud from the Sahara Desert that has mineral components such as phosphorus and iron, components that are very useful to fertilize the fields in many parts of the world, because this western Shara dust travels to distant regions, reaching far places such as the Caribbean islands, México, and sometimes, parts of the United States, as was the case the last year.