According to the Textbook, Why Are Large Areas of East

According to the textbook, why are large areas of east Africa devoid of cattle today?

A) Changes introduced by European intruders caused the spread of the tsetse fly, which carries illnesses that are fatal to both humans and livestock.
B) The natives of the region practiced a scorched earth policy of defense against European intruders in which they slaughtered their own herds and burned down their own villages.
C) European cattle farmers resented the cheap imports that flowed into the continent after colonization, and colonial administrators were pressured to destroy millions of animals owned by natives.
D) African cattle transmitted diseases to Europeans that the native peoples had resistance to, and the subsequent substitution of European cattle breeds for African breeds proved unsuccessful.