Which of the following colonial policy contribute further to today’s agricultural underdevelopment in Africa ?

I. Colonial governments compelled farmers to grow selected crops
II. Colonialism often changed traditional land tenure systems from individual control to communal
III. Colonialists failed to train African agricultural scientists and managers
IV. Research and development concentrated on food production and small farmers and herders.
A. I and II only
B. I and III only
C. III and IV only
D. II and III only