Final answer:
The best conclusion supported by the passage is that the Arab-Israeli conflict can be traced in part to earlier British promises.
Step-by-step explanation:
The best conclusion supported by the passage is D. The Arab-Israeli conflict can be traced in part to earlier British promises. The passage states that in 1917, the British government issued the Balfour Declaration, which expressed support for a “national home” for Jewish people in Palestine. This promise to establish a Jewish homeland caused tension and conflicts between Jews and Arabs in the region, which continue to this day.