Dr. Sayreâ€™s lecture recounted several little-known episodes in the relations between nations that illustrates what is wrong with alliances and treaties that do not have popular support.
(A) relations between nations that illustrates
(B) relation of one nation with another that illustrates
(C) relations between nations that illustrate
(D) relation of one nation with another and illustrate
(E) relations of nations that illustrates
B is correct.
This question is not testing "between" or "among" rather it is testing "one"/other/another".
Here one another is required because the relation is between one nation with more than two countries.
use one-the other for two choices
use one-another for more than two choices