Why was Sub-Saharan Africa chosen as the location for this trial?

Why was Sub-Saharan Africa chosen as the location for this trial? Sub-Saharan Africa is chosen for these trials because 22 million people have HIV out of the 30 million total people that have HIV making up about 70%, and due to it being a developing country the trials are help to less ethical practice.

Explanation:

d.

yeet yeet yeet

option c (nickel) is not found in earth's crust. the earth's crust basically contains eight (8) elements namely: oxygen, silicon, aluminum, iron, calcium, sodium, potassium and magnesium (listed in order of abundance).