Answer:
D. anti-Assad, anti-ISIS
Step-by-step explanation:
Throughout the Syrian Civil War, which started in 2011 and is still ongoing, the United States has always been in opposition to the regime of Bashar Al Assad.
The reason is that Assad's regime is pro-Russia, and Russia is one of the most important geopolitical adversaries of the United States (the other being China).
The United States also became anti-ISIS when this terrorist group emerged. The United States was crucial in the eventual almost total defeat of ISIS. Currently, ISIS only holds a small patch of land in central Syria.