I am almost positive that it is letter D. Monounsaturated fats are good for weight loss, reduce inflammation, and can lower your risks of heart disease. You can find monounsaturated fats in olive oil, avocados, and some nuts. Polyunsaturated fats are fats in which the constituent hydrocarbon chain possesses two or more carbon–carbon double bonds. You can find this kind of fat in most nuts, fish, oysters, and seed oils. I hope this helps. :)
