Final answer:
One serving of grain products such as cooked rice, bulgur, or quinoa is ½ cup or 125 grams.
Step-by-step explanation:
When it comes to servings of grain products like cooked rice, bulgur, or quinoa, a common reference is the healthy eating guidelines which suggest filling a quarter of your plate with grains and making at least half of your daily grain intake whole grains. This includes foods like 100% whole wheat bread and brown rice. Per nutritional label standards, a serving of grain such as this would generally be 120 mL or ½ cup, which approximately translates to 125 grams. Therefore, the correct answer to how much cooked rice, bulgur, or quinoa amounts to one serving is A) ½ cup, 125g.