The Arab Spring is widely believed to have stemmed from dissatisfaction with the rule of local governments, though some have speculated that wide gaps in income levels may have had a hand as well. Issues such as political corruption, human rights violations, unemployment, and educated but dissatisfied youth may have been responsible as well._____________

The Arab Spring, which refers to a series of movements in the Arab world against the government, are attributed to the dissatisfaction among the people towards the local governments. The passage states that income inequalities might have been responsible as well. Lastly the passage attributes political corruption, human rights violations, unemployment, and dissatisfied youth to be a cause in the uprisings. 

Option A focuses solely on the youth unrest despite the multiple variables talked about before, and cannot follow in the blank. Option B mentions Iran, but no country in particular has been mentioned under the umbrella term 'Arab' in the paragraph, unless we do not find a better option, this is likely incorrect. Option C is likely incorrect as wide income gaps have already been mentioned in the paragraph. Option D summarizes the points mentioned in the paragraph and does not narrow it down to one country in particular, and is therefore the correct answer.