The correct answer is, the advantage for the Allies in controlling the North Africa region in 1943, was that it allowed the allied forces the control of the Suez canal, a strategic point for shipping navigation.
That was of the utmost important for the allies because the canal represented an importance pass for the transportation of people and war supplies. This maintained the possibility to transport oil from the Middle East and other materials needed for the war that were found in Asia. Oil was very important for the Allied armies and their maneuvers.
