The answer is all of these
There are many things that can affect ocean currents. Particularly wind. Changes in temperature with air currents and tides affect it as well.
They basically want you to write a newsletter over Africa's water drying up, lose of vegetation and their wildlife dying (poaching). They want you to go in-depth about how the climate changing and the things that they do in their everyday life are affecting their living structure!
The answer is red blood cells