Explanation:

Explain 
In the given statements, statement I depicts the UAE’s involvement in conflicts across the region and statement II statement states a possible effect.
Applying the elimination technique, let’s check the relevance of each of the options one by one.
Possibility 1.
In spite of the UAE has involvement in conflicts across the region, both openly in Yemen and in Syria, its rulers have possibly realised the need to squeeze more revenue out of every barrel of oil.
Though the synthesis made above looks fine, it doesn’t not however keeps the flow intact. This eliminates options A and D.
Possibility 2.
Since the UAE’s rulers have possibly realised the need to squeeze more revenue out of every barrel of oil, it has involvement in conflicts across the region, both openly in Yemen and in Syria.
Once again an example of a grammatical correct formation but it too doesn’t make any sense here. This eliminates option B as well.
Possibility 3
Given the UAE’s involvement in conflicts across the region, both openly in Yemen and in Syria, its rulers have possibly realised the need to squeeze more revenue out of every barrel of oil.
Clearly, the above synthesis is both grammatically and logically correct and keeps the chain of thoughts intact.

Option C is hence the correct answer.