Bridgewater is not your average hedge fund. In my day job, I have had quite a few meetings with them and there approach is extremely thorough and very interesting. I would definitely recommend Ray Dalio's books ("Principles" and 'a template for understanding big debt crises") for a better understanding of both markets and Bridgewater.
Pure Alpha uses a combination of over 125 different trading strategies. As they say, they implement their decisions based on their understanding of the economic machine (see youtube link below). They identify timeless and universal drivers of markets, combining their views on macroeconomic drivers, intermarket action and capital flows. I would be surprised if there weren't a number of options strategies between the 125 strategies employed, but they will likely differ substantially from the SO approach.