World War I caused the suspension of the gold standard for fixed international exchange rates because the war:

a. cost too much money.

b. interrupted the free movement of gold.

c. lasted too long.

d. used up too much gold by warring countries to buy armaments.

Option B, interrupted the free movement of gold, is the right answer.

Explanation:

A monetary system in which the standard economy unit is based on a fixed amount of gold is known as the Gold Standard. Throughout the Nineteenth and the Twentieth Century, many countries used this system of Gold Standard. With the end of 1913, the gold standard was at its zenith but the First World War caused many countries to abandon it.