Aviation and Airport Security Practice Test.

Explanation During World War I, the southern part of Modern Iran was ruled by the British due to their imperial control over the region at the time. The other options, such as the Russians, Ottomans, and Germans, may have had involvement in the region but they did not rule over it during this time period. It is important to note that Iran was caught in between the confrontations and influence of these major powers during World War I, but the British were the dominant ruling force in the southern region of the country.