Answer:
D, demonstrating American strength to the world.
For agriculture,and China people really favour rice,so if there is no land,there wouldn't be an exact place for them to plant for production of rice.
The name of the wide area of the dry land located along the southern edge of the Sahara is B) Sahel.Hope this helps.
The answer you are looking for is
Democratic Republic of Congo: which gained its independence in 1960
Ghana: which gained its independence 1957
Nigeria: which gained its independence 1960
Hope this helped :D