The correct answer is D) The era of British control.
The title that would best suit the period in Iraqi history from 1918 through 1932 is the era of British control.
British controlled Iraq after World War 1. Before that Iraq was ruled by the Ottoman Empire. But the League of Nations decided that England should govern Iraq in 1920. So British protection was established in Iraq from 1921 to 1932 when Iraq was granted its independence. However, the British continued exerting its influence in the economic and political life of Iraq, and as a consequence of this, many people protested.